Document and Entity Information	6 Months Ended
Document and Entity Information	Jun. 30, 2012	Aug. 06, 2012
Document and Entity Information [Abstract]
Entity Registrant Name	NEKTAR THERAPEUTICS
Entity Central Index Key	0000906709
Document Type	10-Q
Document Period End Date	Jun. 30, 2012
Amendment Flag	false
Document Fiscal Year Focus	2012
Document Fiscal Period Focus	Q2
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding		114,909,529

Condensed Consolidated Balance Sheets (Unaudited) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2012	Dec. 31, 2011
Current assets:
Cash and cash equivalents	$ 136,154	$ 15,312
Short-term investments	296,720	225,856
Accounts receivable	11,361	4,938
Inventory	14,715	12,656
Other current assets	9,341	17,944
Total current assets	468,291	276,706
Long-term investments	44,245	173,768
Property and equipment, net	73,713	78,576
Goodwill	76,501	76,501
Other assets	5,693	999
Total assets	668,443	606,550
Current liabilities:
Accounts payable	3,118	3,019
Accrued compensation	10,519	12,807
Accrued expenses	7,636	6,669
Accrued clinical trial expenses	12,607	11,953
Deferred revenue, current portion	20,691	19,643
Convertible subordinated notes	214,955	214,955
Other current liabilities	7,335	6,486
Total current liabilities	276,861	275,532
Capital lease obligations, less current portion	13,174	14,582
Liability related to sale of future royalties	127,686
Deferred revenue, less current portion	108,215	108,188
Other long-term liabilities	10,223	10,437
Total liabilities	536,159	408,739
Commitments and contingencies
Stockholders' equity:
Preferred stock, 10,000 shares authorized, $0.0001 par value; 3,100 shares designated Series A and no shares issued or outstanding at December 31, 2011; no shares designated, issued or outstanding at June 30, 2012
Common stock, $0.0001 par value; 300,000 authorized; 114780 shares and 114,485 shares issued and outstanding at June 30, 2012 and December 31, 2011, respectively	11	11
Capital in excess of par value	1,606,800	1,597,428
Accumulated other comprehensive loss	(620)	(1,103)
Accumulated deficit	(1,473,907)	(1,398,525)
Total stockholders' equity	132,284	197,811
Total liabilities and stockholders' equity	$ 668,443	$ 606,550

Condensed Consolidated Balance Sheets (Unaudited) (Parenthetical) (USD $) In Thousands, except Per Share data, unless otherwise specified	Jun. 30, 2012	Dec. 31, 2011
Condensed Consolidated Balance Sheets [Abstract]
Preferred stock, par value	$ 0.0001	$ 0.0001
Preferred stock, shares authorized	10,000	10,000
Preferred stock, shares designated	0	3,100
Preferred stock, shares issued
Preferred stock, shares outstanding
Common stock, par value	$ 0.0001	$ 0.0001
Common stock, shares authorized	300,000	300,000
Common stock, shares issued	114,780	114,485
Common stock, shares outstanding	114,780	114,485

Condensed Consolidated Statements of Operations (Unaudited) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011
Revenue:
Product sales and royalties	$ 13,453	$ 11,008	$ 23,575	$ 15,801
License, collaboration and other	10,231	6,323	18,058	12,829
Total revenue	23,684	17,331	41,633	28,630
Operating costs and expenses:
Cost of goods sold	7,203	8,140	15,910	11,403
Research and development	33,201	32,270	68,286	62,446
General and administrative	10,268	11,185	20,682	22,912
Impairment of long-lived assets			1,675
Total operating costs and expenses	50,672	51,595	106,553	96,761
Loss from operations	(26,988)	(34,264)	(64,920)	(68,131)
Non-operating income (expense):
Interest income	630	529	1,262	961
Interest expense	(7,931)	(2,570)	(12,264)	(5,155)
Other income (expense), net	97	(16)	757	118
Total non-operating expense	(7,204)	(2,057)	(10,245)	(4,076)
Loss before provision for income taxes	(34,192)	(36,321)	(75,165)	(72,207)
Provision for income taxes	93	60	217	208
Net loss	$ (34,285)	$ (36,381)	$ (75,382)	$ (72,415)
Basic and diluted net loss per share	$ (0.30)	$ (0.32)	$ (0.66)	$ (0.65)
Weighted average shares outstanding used in computing basic and diluted net loss per share	114,649	114,153	114,590	111,430

Condensed Consolidated Statements of Comprehensive Loss (Unaudited) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011
Condensed Consolidated Statements of Comprehensive Loss [Abstract]
Comprehensive loss	$ (34,862)	$ (36,433)	$ (74,899)	$ (72,617)

- Definition

The change in equity [net assets] of a business enterprise during a period from transactions and other events and circumstances from non-owner sources which are attributable to the reporting entity. It includes all changes in equity during a period except those resulting from investments by owners and distributions to owners, but excludes any and all transactions which are directly or indirectly attributable to that ownership interest in subsidiary equity which is not attributable to the parent.

+ References+ Details

Condensed Consolidated Statements of Cash Flows (Unaudited) (USD $) In Thousands, unless otherwise specified	6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011
Cash flows from operating activities:
Net loss	$ (75,382)	$ (72,415)
Adjustments to reconcile net loss to net cash used in operating activities:
Non-cash interest expense on liability related to sale of future royalties	7,278
Non-cash royalty revenue related to sale of future royalties	(3,469)
Stock-based compensation	8,035	9,682
Depreciation and amortization	6,952	7,649
Impairment of long-lived assets	1,675
Other non-cash transactions	565	620
Changes in operating assets and liabilities:
Accounts receivable	(6,423)	16,642
Inventory	(2,059)	(2,531)
Other assets	8,176	(2,191)
Accounts payable	80	(3,149)
Accrued compensation	(2,288)	183
Accrued expenses	191	2,371
Accrued clinical trial expenses	654	1,688
Deferred revenue	1,075	(7,549)
Other liabilities	(269)	(658)
Net cash used in operating activities	(55,209)	(49,658)
Cash flows from investing activities:
Purchases of investments	(120,410)	(509,681)
Maturities of investments	179,766	156,962
Sales of investments		180,478
Purchases of property and equipment	(3,172)	(6,845)
Net cash provided by (used in) investing activities	56,184	(179,086)
Cash flows from financing activities:
Payments of loan and capital lease obligations	(1,151)	(934)
Proceeds from sale of future royalties, net of transaction costs	119,589
Issuance of common stock, net of issuance costs	1,337	223,549
Net cash provided by financing activities	119,775	222,615
Effect of exchange rates on cash and cash equivalents	92
Net increase (decrease) in cash and cash equivalents	120,842	(6,129)
Cash and cash equivalents at beginning of period	15,312	17,755
Cash and cash equivalents at end of period	136,154	11,626
Supplemental Cash Flow Information [Abstract]
Cash paid for interest	$ 5,179	$ 5,371

Organization and Summary of Significant Accounting Policies

6 Months Ended

Jun. 30, 2012

Organization and Summary of Significant Accounting Policies [Abstract]

Organization and Summary of Significant Accounting Policies

Note 1 — Organization and Summary of Significant Accounting Policies

Organization

We are a clinical-stage biopharmaceutical company headquartered in San Francisco, California and incorporated in Delaware. We are developing a pipeline of drug candidates that utilize our PEGylation and advanced polymer conjugate technology platforms with the objective to improve the benefits of drugs for patients.

Our research and development activities have required significant resources to date and are expected to continue to require significant resources. As a result, we expect to continue to incur substantial losses and negative cash flows from operations in the future. We have financed our operations primarily through cash from licensing, collaboration and manufacturing agreements and debt and equity financings. At June 30, 2012, we had approximately $477.1 million in cash, cash equivalents, and investments in marketable securities and $239.0 million in indebtedness, including $215.0 million in outstanding convertible subordinated notes due September 28, 2012. On July 11, 2012, we issued $125.0 million in aggregate principal amount of 12.0% senior secured notes due July 2017. We retired $42.5 million in principal amount of the convertible subordinated notes in exchange for the same principal amount of the senior secured notes. We intend to use the proceeds from the issuance of these senior secured notes and our existing cash to repay the remaining $172.5 million in principal amount of the convertible subordinated notes in full at maturity.

Basis of Presentation and Principles of Consolidation

Our consolidated financial statements include the financial position, results of operations and cash flows of our wholly-owned subsidiaries: Nektar Therapeutics (India) Private Limited (Nektar India) and Nektar Therapeutics UK Limited. All intercompany accounts and transactions have been eliminated in consolidation.

We prepared our Condensed Consolidated Financial Statements following the requirements of the Securities and Exchange Commission (SEC) for interim reporting. As permitted under those rules, certain footnotes or other financial information that are normally required by U.S. generally accepted accounting principles (GAAP) for annual periods can be condensed or omitted. In the opinion of management, these financial statements include all normal and recurring adjustments that we consider necessary for the fair presentation of our financial position and operating results.

Our Condensed Consolidated Financial Statements are denominated in U.S. dollars. Accordingly, changes in exchange rates between the applicable foreign currency and the U.S. dollar will affect the translation of each foreign subsidiary’s financial results into U.S. dollars for purposes of reporting our consolidated financial results. Translation gains and losses are included in accumulated other comprehensive loss in the stockholders’ equity section of the Condensed Consolidated Balance Sheets. To date, such cumulative currency translation adjustments have not been material to our consolidated financial position.

On January 1, 2012, we were required to adopt new accounting guidance related to the presentation of comprehensive income that prohibits the presentation of other comprehensive income (OCI) in the statement of stockholders’ equity and instead, provides the option of presenting OCI in a continuous statement of comprehensive income or as two separate consecutive statements. Our comprehensive loss consists of our net loss plus our foreign currency translation gains and losses and unrealized holding gains and losses on available-for-sale securities, neither of which were significant during the three and six months ended June 30, 2012 and 2011. This change had no impact on our financial position or results of operations.

The accompanying Condensed Consolidated Financial Statements are unaudited. The Condensed Consolidated Balance Sheet data as of December 31, 2011 was derived from the audited consolidated financial statements which are included in our Annual Report on Form 10-K for the year ended December 31, 2011 filed with the SEC on February 29, 2012. The information included in this quarterly report on Form 10-Q should be read in conjunction with the consolidated financial statements and the accompanying notes to those financial statements included in our Annual Report on Form 10-K for the year ended December 31, 2011.

Revenue, expenses, assets, and liabilities can vary during each quarter of the year. The results and trends in these interim Condensed Consolidated Financial Statements may not be indicative of the results to be expected for the full year or any other periods.

Use of Estimates

The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. Actual results could differ materially from those estimates. On an ongoing basis, we evaluate our estimates, including those related to deferred revenue recognition periods, inventories, the impairment of investments, the impairment of goodwill and long-lived assets, contingencies, estimated interest expense from our liability related to our sale of future royalties, stock-based compensation, and ongoing litigation, among other estimates. We base our estimates on historical experience and on other assumptions that management believes are reasonable under the circumstances. These estimates form the basis for making judgments about the carrying values of assets and liabilities when these values are not readily apparent from other sources.

Reclassifications

Certain items previously reported in specific financial statement captions have been reclassified to conform to the current period presentation. Such reclassifications do not impact previously reported revenue, operating loss or net loss or total assets, liabilities or stockholders’ equity.

Segment Information

We operate in one business segment which focuses on applying our technology platforms to improve the performance of established and novel drug candidates. We operate in one segment because our business offerings have similar economics and other characteristics, including the nature of products and manufacturing processes, types of customers, distribution methods and regulatory environment. We are comprehensively managed as one business segment by our Chief Executive Officer and his management team.

Significant Concentrations

Our customers are primarily pharmaceutical and biotechnology companies that are located in the U.S. and Europe. Our accounts receivable balance contains billed and unbilled trade receivables from product sales and royalties, as well as time and materials based billings from collaborative research and development agreements. We provide for an allowance for doubtful accounts by reserving for specifically identified doubtful accounts. We generally do not require collateral from our customers. We perform a regular review of our customers’ payment histories and associated credit risk. We have not experienced significant credit losses from our accounts receivable and our allowance for doubtful accounts was not significant at either June 30, 2012 or December 31, 2011.

We are dependent on our suppliers and contract manufacturers to provide raw materials, drugs and devices of appropriate quality and reliability and to meet applicable contract and regulatory requirements. In certain cases, we rely on single sources of supply of one or more critical materials. Consequently, in the event that supplies are delayed or interrupted for any reason, our ability to develop and produce our drug candidates or our ability to meet our supply obligations could be significantly impaired, which could have a material adverse effect on our business, financial condition and results of operations.

Revenue

We enter into arrangements with pharmaceutical and biotechnology partners that may involve multiple deliverables. Our arrangements may contain one or more of the following elements: upfront fees, contract research and development, milestone payments, manufacturing and supply payments, royalties, and license fees. Each deliverable in the arrangement is evaluated to determine whether it meets the criteria to be accounted for as a separate unit of accounting or whether it should be combined with other deliverables. Revenue is recognized separately for each element.

On January 1, 2011, we adopted on a prospective basis Accounting Standards Update (ASU) 2009-13, which amends the criteria to identify separate units of accounting within Subtopic 605-25, “Revenue Recognition-Multiple-Element Arrangements.” Under this guidance, at the inception of each new multiple-element arrangement or the material modification of an existing multiple-element arrangement, we allocate all consideration received under multiple-element arrangements to all units of accounting based on the relative selling price method, generally based on our best estimate of selling price (ESP). The objective of ESP is to determine the price at which we would transact a sale if the product or service was sold on a stand-alone basis. We determine ESP for the elements in our collaboration arrangements by considering multiple factors including, but not limited to, technical complexity of the performance obligation and similarity of elements to those performed under previous arrangements. Since we apply significant judgment in arriving at the ESPs, any material change in our estimates would significantly affect the allocation of the total consideration to the different elements of a multiple element arrangement.

Product sales and royalties

Product sales are primarily derived from cost-plus and fixed price manufacturing and supply agreements with our collaboration partners and revenue is recognized when there is persuasive evidence that an arrangement exists, delivery has occurred, the price is fixed or determinable, and collection is reasonably assured. We have not experienced any significant returns from our customers.

Generally, we are entitled to royalties from our partners based on their net sales of approved drugs. We recognize royalty revenue when the cash is received or the royalty amount is otherwise known or when the royalty amount to be received is estimable and collection is reasonably assured.

License, collaboration and other

Upfront fees received for ongoing obligations, such as manufacturing and supply obligations, under our license and collaborative agreements are recognized ratably over our expected performance period under each respective arrangement. We make our best estimate of the period over which we expect to fulfill our performance obligations, which may include technology transfer assistance, research activities, clinical development activities, and manufacturing activities from development through the commercialization of the product. Given the uncertainties of these collaborative arrangements, significant judgment is required to determine the duration of the performance period.

On January 1, 2011, we elected to prospectively adopt ASU 2010-17, “Milestone Method of Revenue Recognition”. Under the milestone method, contingent consideration received from the achievement of a substantive milestone is recognized in its entirety in the period in which the milestone is achieved, which we believe is consistent with the substance of our performance under our various license and collaboration agreements. A milestone is defined as an event (i) that can only be achieved based in whole or in part either on the entity’s performance or on the occurrence of a specific outcome resulting from the entity’s performance, (ii) for which there is substantive uncertainty at the date the arrangement is entered into that the event will be achieved, and (iii) that would result in additional payments being due to the entity. A milestone is substantive if the consideration earned from the achievement of the milestone is consistent with our performance required to achieve the milestone or the increase in value to the collaboration resulting from our performance, relates solely to our past performance, and is reasonable relative to all of the other deliverables and payments within the arrangement.

Our license and collaboration agreements with our partners provide for payments to us upon the achievement of development milestones, such as the completion of clinical trials or regulatory submissions, approvals by health authorities, and commercial launches of drug candidates. Given the challenges inherent in developing and obtaining approval for drug products and in achieving commercial launches, there was substantial uncertainty whether any such milestones would be achieved at the time of execution of these licensing and collaboration agreements. In addition, we evaluated whether the development milestones met the remaining criteria to be considered substantive. As a result of our analysis, we consider our development milestones under all of our license and collaboration agreements to be substantive and, accordingly, we expect to recognize as revenue future payments received from such milestones only if and as each milestone is achieved.

Our license and collaboration agreements with certain partners also provide for contingent payments to us based solely upon the performance of the respective partner. For such contingent amounts we expect to recognize the payments as revenue when earned under the applicable contract, provided that collection is reasonably assured.

Our license and collaboration agreements with our partners also provide for payments to us upon the achievement of specified sales volumes of approved drugs. We consider these payments to be similar to royalty payments and we will recognize such sales-based payments upon achievement of such sales volumes, provided that collection is reasonably assured.

Income Taxes

We account for income taxes under the liability method; under this method, deferred tax assets and liabilities are determined based on differences between financial reporting and tax reporting bases of assets and liabilities and are measured using enacted tax rates and laws that are expected to be in effect when the differences are expected to reverse. Realization of deferred tax assets is dependent upon future earnings, the timing and amount of which are uncertain. We record a valuation allowance against deferred tax assets to reduce their carrying value to an amount that is more likely than not to be realized. When we establish or reduce the valuation allowance related to the deferred tax assets, our provision for income taxes will increase or decrease, respectively, in the period such determination is made.

For the three and six months ended June 30, 2012 and 2011, we recorded an income tax provision for our Nektar India operations at an effective tax rate of approximately 33% for each period. The U.S. federal deferred tax assets generated from our net operating losses have been fully reserved as we believe it is not more likely than not that the benefit will be realized.

- Definition

The entire disclosure for organization, consolidation and basis of presentation of financial statements disclosure.

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+ Details

Cash, Cash Equivalents and Available-For-Sale Investments

6 Months Ended

Jun. 30, 2012

Cash, Cash Equivalents, and Available-For-Sales Investments [Abstract]

Cash, Cash Equivalents, and Available-For-Sale Investments

Note 2 — Cash, Cash Equivalents, and Available-For-Sale Investments

Cash, cash equivalents, and available-for-sale investments are as follows (in thousands):


	Estimated Fair Value at
	June 30, 2012		December 31, 2011
Cash and cash equivalents	$	136,154	$	15,312
Short-term investments		296,720		225,856
Long-term investments		44,245		173,768

Total cash, cash equivalents, and available-for-sale investments	$	477,119	$	414,936

Our portfolio of cash, cash equivalents, and available-for-sale investments includes (in thousands):


	Estimated Fair Value at
	June 30, 2012		December 31, 2011
Corporate notes and bonds	$	314,473	$	344,427
U.S. corporate commercial paper		19,984		9,464
Obligations of U.S. government agencies		5,003		44,230
Obligations of U.S. states and municipalities		1,505		1,503
Cash and money market funds		136,154		15,312

Total cash, cash equivalents, and available-for-sale investments	$	477,119	$	414,936

The following table summarizes our portfolio of available-for-sale investments reported as short-term and long-term investments by contractual maturity (in thousands):


	Estimated Fair Value at
	June 30, 2012		December 31, 2011
Less than one year	$	296,720	$	213,386
Greater than one year but less than two years		44,245		186,238

Total available-for-sale investments	$	340,965	$	399,624

We invest in liquid, high quality debt securities. Our investments in debt securities are subject to interest rate risk. To minimize the exposure due to an adverse shift in interest rates, we invest in securities with maturities of two years or less and maintain a weighted average maturity of one year or less. Investments in securities with remaining maturities of less than one year, or where our intent is to use the investments to fund current operations, or to make them available for current operations, are classified as short-term investments.

Gross unrealized gains and losses were not significant at either June 30, 2012 or December 31, 2011. During the six month periods ended June 30, 2012 and 2011, we sold available-for-sale securities totaling nil and $180.5 million, respectively, and realized gains and losses were not significant in any of the three and six month periods ended June 30, 2012 and 2011. The cost of securities sold is based on the specific identification method.

All of our investments are categorized as Level 1 or Level 2, as explained in the table below. We use a market approach to value our Level 2 investments. The disclosed fair value related to our investments is based primarily on the reported fair values in our period-end brokerage statements, which are based on market prices from a variety of industry standard data providers and generally represent quoted prices for similar assets in active markets or have been derived from observable market data. We independently validate these fair values using available market quotes and other information. During the three and six month periods ended June 30, 2012 and 2011, there were no transfers between Level 1 and Level 2 of the fair value hierarchy.

The following table represents the fair value hierarchy for our financial assets measured at fair value on a recurring basis as of June 30, 2012 and December 31, 2011 (in thousands):


As of June 30, 2012:	Level 1		Level 2		Level 3		Total
Money market funds	$	135,509	$	—	$	—	$	135,509
U.S. corporate commercial paper		—		19,984		—		19,984
Corporate notes and bonds		—		314,473		—		314,473
Obligations of U.S. government agencies		—		5,003		—		5,003
Obligations of U.S. states and municipalities		—		1,505		—		1,505

Cash equivalents and available-for-sale investments	$	135,509	$	340,965	$	—	$	476,474
Cash								645

Cash, cash equivalents, and available-for-sale investments							$	477,119


As of December 31, 2011:	Level 1		Level 2		Level 3		Total
Money market funds	$	13,950	$	—	$	—	$	13,950
U.S. corporate commercial paper		—		9,464		—		9,464
Corporate notes and bonds		—		344,427		—		344,427
Obligations of U.S. government agencies		—		44,230		—		44,230
Obligations of U.S. states and municipalities		—		1,503		—		1,503

Cash equivalents and available-for-sale investments	$	13,950	$	399,624	$	—	$	413,574
Cash								1,362

Cash, cash equivalents, and available-for-sale investments							$	414,936


Level 1 —		Quoted prices in active markets for identical assets or liabilities.
Level 2 —		Inputs other than Level 1 that are observable, either directly or indirectly, such as quoted prices for similar assets or liabilities; quoted prices in markets that are not active; or other inputs that are observable or can be corroborated by observable market data for substantially the full term of the assets or liabilities.
Level 3 —		Unobservable inputs that are supported by little or no market activity and that are significant to the fair value of the assets or liabilities.

- Definition

The entire disclosure for the fair value of financial instruments (as defined), including financial assets and financial liabilities (collectively, as defined), and the measurements of those instruments as well as disclosures related to the fair value of non-financial assets and liabilities. Such disclosures about the financial instruments, assets, and liabilities would include: (1) the fair value of the required items together with their carrying amounts (as appropriate); (2) for items for which it is not practicable to estimate fair value, disclosure would include: (a) information pertinent to estimating fair value (including, carrying amount, effective interest rate, and maturity, and (b) the reasons why it is not practicable to estimate fair value; (3) significant concentrations of credit risk including: (a) information about the activity, region, or economic characteristics identifying a concentration, (b) the maximum amount of loss the entity is exposed to based on the gross fair value of the related item, (c) policy for requiring collateral or other security and information as to accessing such collateral or security, and (d) the nature and brief description of such collateral or security; (4) quantitative information about market risks and how such risks are managed; (5) for items measured on both a recurring and nonrecurring basis information regarding the inputs used to develop the fair value measurement; and (6) for items presented in the financial statement for which fair value measurement is elected: (a) information necessary to understand the reasons for the election, (b) discussion of the effect of fair value changes on earnings, (c) a description of [similar groups] items for which the election is made and the relation thereof to the balance sheet, the aggregate carrying value of items included in the balance sheet that are not eligible for the election; (7) all other required (as defined) and desired information.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 107

-Paragraph 3, 10, 14, 15

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

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Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

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-Paragraph 32, 33, 34

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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Reference 12: http://www.xbrl.org/2003/role/presentationRef

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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+ Details

Inventory

6 Months Ended

Jun. 30, 2012

Inventory [Abstract]

Inventory

Note 3 — Inventory

Inventory consists of the following (in thousands):


	June 30, 2012		December 31, 2011
Raw materials	$	10,181	$	9,754
Work-in-process		2,976		1,219
Finished goods		1,558		1,683

Total	$	14,715	$	12,656

Inventory is generally manufactured upon receipt of firm purchase orders from our collaboration partners. Inventory includes direct materials, direct labor, and manufacturing overhead and is determined on a first-in, first-out basis. Raw materials include manufactured intermediate materials which are subsequently combined with other materials to make work-in-process and finished goods inventory. Inventory is stated at the lower of cost or market and is net of reserves determined using specific identification plus an estimated reserve for potential defective or excess inventory based on historical experience or projected usage.

- Definition

The entire disclosure for inventory. This may include, but is not limited to, the basis of stating inventory, the method of determining inventory cost, the major classes of inventory, and the nature of the cost elements included in inventory. If inventory is stated above cost, accrued net losses on firm purchase commitments for inventory and losses resulting from valuing inventory at the lower-of-cost-or-market may also be included. For LIFO inventory, may disclose the amount and basis for determining the excess of replacement or current cost over stated LIFO value and the effects of a LIFO quantities liquidation that impacts net income.

+ References+ Details

Liability related to sale of future royalties

6 Months Ended

Jun. 30, 2012

Note 4 — Liability related to sale of future royalties

On February 24, 2012, we entered into a Purchase and Sale Agreement (the Purchase and Sale Agreement) with RPI Finance Trust (RPI), an affiliate of Royalty Pharma, pursuant to which we sold, and RPI purchased, our right to receive royalty payments (the Royalty Entitlement) arising from the worldwide net sales, from and after January 1, 2012, of (a) CIMZIA^®, under Nektar’s license, manufacturing and supply agreement with UCB Pharma (UCB), and (b) MIRCERA^®, under Nektar’s license, manufacturing and supply agreement with F. Hoffmann-La Roche Ltd and Hoffmann-La Roche Inc. (together referred to as Roche). We received an aggregate cash purchase price for the Royalty Entitlement of $124.0 million. As part of this sale, we incurred approximately $4.4 million in transaction costs, which will be amortized to interest expense over the estimated life of the Purchase and Sale Agreement. As is further described below, although we sold all of our rights to receive royalties from the CIMZIA ^® and MIRCERA^® products, we will continue to account for these royalties as revenue and recorded the $124.0 million in proceeds from this transaction as a liability as a result of our ongoing manufacturing and supply obligations related to the generation of these royalties.

The following table shows the activity within the liability account:


	Six months ended June 30, 2012
Liability related to sale of future royalties - beginning balance	$	—
Proceeds from sale of future royalties		124,000
Non-cash interest expense		7,155
CIMZIA^® and MIRCERA^® royalties remitted to RPI		(3,469	)

Liability related to sale of future royalties - ending balance	$	127,686

Pursuant to the Purchase and Sale Agreement, we are required to pay to RPI (a) $3.0 million if certain worldwide net sales thresholds of MIRCERA^® for the 12 month period ending on December 31, 2012 are not achieved and (b) up to an additional $7.0 million if certain worldwide net sales thresholds of MIRCERA^® for the 12 month period ending on December 31, 2013 are not achieved. The Purchase and Sale Agreement grants RPI the right to receive certain reports and other information relating to the Royalty Entitlement and contains other representations and warranties, covenants and indemnification obligations that are customary for a transaction of this nature. In particular, if we breach our obligations under the Purchase and Sale Agreement, we could be required to pay damages to RPI that are not limited to the purchase price we received in the sale transaction.

Except as described above, RPI is entitled only to the future royalty payments arising from sales of CIMZIA^® and MIRCERA ^®, pursuant to our agreements with UCB and Roche. However, we have determined that we have significant continuing involvement in the generation of these future royalty payments through our ongoing manufacturing and supply obligations. As a result, we recorded the $124.0 million as a long-term liability (Royalty Obligation) on our Condensed Consolidated Balance Sheet that will be amortized using the interest method over the estimated life of the Purchase and Sale Agreement. We believe the carrying amount of the Royalty Obligation is consistent with its fair value. The model used to estimate the fair value of the rights sold to RPI required us to make estimates regarding, among other things, the assumptions market participants would make regarding the timing, probability and amount of future royalties, as well as the appropriate financial discount rates. We consider the assumptions and estimates used in this analysis to fall within Level 3 of the fair value hierarchy.

As a result of this liability accounting, even though the royalties from UCB and Roche will be remitted directly to RPI starting in the second quarter of 2012 for royalties arising from product sales in the first quarter of 2012, we will continue to record revenue for these royalties. We recognize royalties from net sales of CIMZIA^® and MIRCERA^® upon notification of the actual royalty amount, which occurs in the quarter after those sales are made. During the six months ended June 30, 2012, we recognized $6.2 million in aggregate royalties from net sales of CIMZIA^® and MIRCERA ^®, of which the $2.7 million recognized in the three months ended March 31, 2012 was retained by Nektar as these amounts resulted from product sales in the fourth quarter of 2011 and the $3.5 million recognized in the three months ended June 30, 2012 was remitted directly to RPI as these amounts resulted from product sales in the first quarter of 2012.

As royalties are remitted to RPI from Roche and UCB, the balance of the Royalty Obligation will be effectively repaid over the life of the agreement. In order to determine the amortization of the Royalty Obligation, we are required to estimate the total amount of future royalty payments to be received by RPI and payments we are required to make to RPI as noted above, if any, over the life of the agreement. The sum of these amounts less the $124.0 million proceeds we received will be recorded as interest expense over the life of the Royalty Obligation. As of March 31, 2012 and June 30, 2012, our estimate of this total interest expense resulted in an effective annual interest rate of approximately 17%. We will periodically assess the estimated royalty payments to RPI from UCB and Roche and to the extent such payments are greater or less than our initial estimates, or the timing of such payments is materially different than our original estimates, we will adjust the amortization of the Royalty Obligation. There are a number of factors that could affect the amount and timing of royalty payments from CIMZIA^® and MIRCERA^®, most of which are not within our control. Such factors include, but are not limited to, changing standards of care, the introduction of competing products, manufacturing or other delays, biosimilar competition, intellectual property matters, adverse events that result in governmental health authority imposed restrictions on the use of the drug products, and other events or circumstances that could result in reduced royalty payments from CIMZIA^® and MIRCERA^®, all of which would result in a reduction of interest expense over the life of the Royalty Obligation. Conversely, if sales of CIMZIA ^® and MIRCERA^® are more than expected, the interest expense recorded by us would be greater over the term of the Royalty Obligation.

Commitments and Contingencies

6 Months Ended

Jun. 30, 2012

Commitments and Contingencies [Abstract]

Commitments and Contingencies

Note 5 — Commitments and Contingencies

Legal Matters

From time to time, we are involved in lawsuits, arbitrations, claims, investigations and proceedings, consisting of intellectual property, commercial, employment and other matters, which arise in the ordinary course of business. We make provisions for liabilities when it is both probable that a liability has been incurred and the amount of the loss can be reasonably estimated. Such provisions are reviewed at least quarterly and adjusted to reflect the impact of settlement negotiations, judicial and administrative rulings, advice of legal counsel, and other information and events pertaining to a particular case. Litigation is inherently unpredictable. If any unfavorable ruling were to occur in any specific period, there exists the possibility of a material adverse impact on the results of operations of that period or on our cash flows and liquidity.

On November 18, 2009, the Research Foundation of the State University of New York (SUNY) filed an action against Nektar in the United States District Court for the Northern District of New York. SUNY seeks to recover amounts it alleges it is owed pursuant to a technology licensing contract between Nektar and SUNY. We dispute SUNY’s claims. Discovery in the matter has closed and we currently expect pre-trial motions (including Nektar’s motion for summary judgment dismissing the action) to be filed in the second half of 2012. In the event the action survives Nektar’s motion, we expect that a trial would be scheduled in the first half of 2013. We believe that SUNY’s claims are without merit. No reasonable estimate of the possible loss or range of loss can be made at this time and no liabilities have been recorded for this matter on our Consolidated Balance Sheets as of June 30, 2012 or December 31, 2011.

Indemnifications in Connection with Commercial Agreements

As part of our collaboration agreements with our partners related to the license, development, manufacture and supply of drugs based on our proprietary technologies, we generally agree to defend, indemnify and hold harmless our partners from and against third party liabilities arising out of the agreement, including product liability (with respect to our activities) and infringement of intellectual property to the extent the intellectual property is developed by us and licensed to our partners. The term of these indemnification obligations is generally perpetual any time after execution of the agreement. There is generally no limitation on the potential amount of future payments we could be required to make under these indemnification obligations.

As part of our pulmonary asset sale to Novartis that was effective as of December 31, 2008, we and Novartis made representations and warranties and entered into certain covenants and ancillary agreements which are supported by an indemnity obligation. Additionally, as part of the sale of our royalty interest in the CIMZIA^® and MIRCERA^® products, we and RPI made representations and warranties and entered into certain covenants and ancillary agreements which are supported by indemnity obligations. In the event it were determined that we breached certain of the representations and warranties or covenants and agreements made by us in any such agreements, we could incur substantial indemnification liabilities depending on the timing, nature, and amount of any such claims.

To date we have not incurred costs to defend lawsuits or settle claims related to these indemnification obligations. If any of our indemnification obligations is triggered, we may incur substantial liabilities. Because the aggregate amount of any potential indemnification obligation is not a stated amount, the overall maximum amount of any such obligations cannot be reasonably estimated. No liabilities have been recorded for these obligations on our Condensed Consolidated Balance Sheets at either June 30, 2012 or December 31, 2011.

- Definition

The entire disclosure for commitments and contingencies.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name FASB Interpretation (FIN)

-Number 14

-Paragraph 3

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef

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-Name Accounting Standards Codification

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

+ Details

License and Collaboration Agreements

6 Months Ended

Jun. 30, 2012

License and Collaboration Agreements [Abstract]

License and Collaboration Agreements

Note 6 — License and Collaboration Agreements

We have entered into various license agreements and collaborative research, development and commercialization agreements with pharmaceutical and biotechnology companies. Under these arrangements, we are entitled to receive license fees, upfront payments, milestone payments when and if certain development or regulatory milestones are achieved, royalties, sales milestones when and if certain annual sales levels are achieved, payment for the manufacture and supply of our proprietary PEGylation materials and/or reimbursement for research and development activities. All of our collaboration agreements are generally cancelable by our partners without significant financial penalty. Our costs of performing these services are generally included in research and development expense.

In accordance with these agreements, we recognized license, collaboration and other revenue as follows (in thousands):


		Three months ended June 30,				Six months ended June 30,
Partner	Drug or Drug Candidate	2012		2011		2012		2011
Baxter Healthcare	Hemophilia	$	4,369	$	561	$	5,053	$	929
Roche	PEGASYS^® and MIRCERA ^®		1,743		1,283		3,124		2,566
Amgen, Inc.	Neulasta^®		1,250		1,250		2,500		2,500
Affymax, Inc.	Omontys		194		452		2,411		903
Bayer Healthcare LLC	BAY41-6551 (Amikacin Inhale)		799		750		1,543		1,500
Other			1,876		2,027		3,427		4,431

License, collaboration, and other revenue		$	10,231	$	6,323	$	18,058	$	12,829

As of June 30, 2012, our collaboration agreements with partners included potential future payments for development milestones totaling approximately $161.1 million, including amounts from our agreements with Bayer and Baxter described below. In addition, we are entitled to receive up to $235.0 million and $75.0 million of contingent payments described below related to NKTR-118 and NKTR-119, respectively, based on development and regulatory events to be pursued and completed solely by AstraZeneca.

Baxter Healthcare: Hemophilia

In September 2005, we entered into an exclusive research, development, license and manufacturing and supply agreement with Baxter Healthcare SA and Baxter Healthcare Corporation (together referred to as Baxter) to develop products designed to improve therapies for Hemophilia A patients using our PEGylation technology. In December 2007, we expanded our agreement with Baxter to include the license of our PEGylation technology with the potential to improve any future products Baxter may develop for Hemophilia B patients. Under the terms of the agreement, we are entitled to research and development funding and are responsible for supplying Baxter with its requirements for our proprietary materials. Baxter is responsible for all clinical development, regulatory, and commercialization expenses. The agreement is terminable by the parties under customary conditions.

As of June 30, 2012, we are entitled to up to $28.0 million of development milestones related to Hemophilia A upon achievement of certain development objectives, as well as sales milestones upon achievement of annual sales targets and royalties based on annual worldwide net sales of products resulting from this agreement. This Hemophilia A program includes BAX-855, which is currently in Phase 1/2 development and which Baxter has targeted to start Phase 3 development by the end of 2012. In prior years, we received upfront payments under the Baxter agreement totaling $4.0 million and $5.0 million related to Hemophilia A and Hemophilia B programs, respectively. As of June 30, 2012, we have deferred revenue of $1.5 million relating to the Hemophilia A program, which we expect to recognize through December 2027, the estimated end of our obligations under this agreement.

In May 2012, Baxter notified us that they intended to cease all future research activities under our agreement related to Hemophilia B. As a result, for the three months ended June 30, 2012, we recognized the remaining $3.9 million deferred revenue balance related to the Hemophilia B program since we have no ongoing or additional performance obligations.

Roche: PEGASYS^® and MIRCERA^®

In February 1997, we entered into a license, manufacturing and supply agreement with Roche, under which we granted Roche a worldwide, exclusive license to certain intellectual property related to our proprietary PEGylation materials used in the manufacture and commercialization of PEGASYS^®. As a result of Roche exercising a license extension option in December 2009, Roche has the right to manufacture all of its requirements for our proprietary PEGylation materials for PEGASYS^® and we perform additional manufacturing, if any, only on an as-requested basis. In connection with Roche’s exercise of the license extension option in December 2009, we received a payment of $31.0 million. As of June 30, 2012, we have deferred revenue of approximately $18.0 million related to this agreement, which we expect to recognize through December 2015, the period through which we are required to provide back-up manufacturing and supply services related to PEGASYS^®.

In February 2012, we entered into a toll-manufacturing agreement with Roche under which we will manufacture the proprietary PEGylation material used by Roche to produce MIRCERA^®. Roche entered into the toll-manufacturing agreement with the objective of establishing us as a secondary back-up source on a non-exclusive basis. Under the terms of the toll-manufacturing agreement, Roche agreed to pay us an upfront payment of $5.0 million and will pay a total of up to $22.0 million in performance-based milestone payments upon our achievement of certain manufacturing readiness, validation and production milestones, including the delivery of specified quantities of PEGylation materials, all of which are scheduled to be completed by the end of January 2013. Roche will also pay us additional consideration for any future orders of the PEGylation materials for MIRCERA^® beyond the initial quantities scheduled to be manufactured and supplied in 2012 and 2013. Roche may terminate the toll-manufacturing agreement due to an uncured material default by us. As of June 30, 2012, we have received $10.0 million in upfront and milestone payments and earned an additional $6.0 million milestone payment which was included in our accounts receivable balance at June 30, 2012. There is a risk that we will not achieve the remaining $11.0 milestone on a timely basis or at all, however we currently expect that we will be able to successfully complete it.

We analyzed the milestone payments under the agreement and determined that they did not meet the criteria for revenue recognition under the milestone method as a result of our continuing manufacturing obligations. We have identified our back-up manufacturing obligation through December 2016 and the delivery of PEGylation materials specified in the agreement in 2012 and early 2013 as the units of accounting in the arrangement. We made our best estimate of the selling prices for these deliverables and have allocated the expected $27.0 million consideration to these items based on the relative selling price method. As of June 30, 2012, we have recognized revenue of $1.6 million related to this agreement, which includes $1.1 million related to the delivery of materials classified as product sales and $0.5 million related to our manufacturing obligation classified as license, collaboration, and other revenue. As of June 30, 2012, we have deferred revenue of approximately $14.4 million, which we expect to recognize through December 2016, the estimated end of our obligations under this agreement.

Amgen, Inc.: Neulasta^®

In October 2010, we amended and restated an existing supply and license agreement by entering into a supply, dedicated suite and manufacturing guarantee agreement (the amended and restated agreement) and a license agreement with Amgen Inc. and Amgen Manufacturing, Limited (together referred to as Amgen). Under the terms of the amended and restated agreement, we guarantee the manufacture and supply of our proprietary PEGylation materials (Polymer Materials) to Amgen in an existing manufacturing suite to be used exclusively for the manufacture of Polymer Materials for Amgen (the Manufacturing Suite) in our manufacturing facility in Huntsville, Alabama (Facility). This supply arrangement is on a non-exclusive basis (other than the use of the Manufacturing Suite and certain equipment) whereby Nektar is free to manufacture and supply the Polymer Materials to any other third party and Amgen is free to procure the Polymer Materials from any other third party. Under the terms of the amended and restated agreement, we received a $50.0 million payment in the fourth quarter of 2010 in return for our guaranteeing the supply of certain quantities of Polymer Materials to Amgen including without limitation the Additional Rights described below and manufacturing fees that are calculated based on fixed and variable components applicable to the Polymer Materials ordered by Amgen and delivered by us. Amgen has no minimum purchase commitments. If quantities of the Polymer Materials ordered by Amgen exceed specified quantities, significant additional payments become payable to us in return for our guaranteeing the supply of additional quantities of the Polymer Materials.

The term of the amended and restated agreement ends on October 29, 2020. In the event we become subject to a bankruptcy or insolvency proceeding, we cease to own or control the Facility, we fail to manufacture and supply or certain other events, Amgen or its designated third party will have the right to elect, among certain other options, to take title to the dedicated equipment and access the Facility to operate the Manufacturing Suite solely for the purpose of manufacturing the Polymer Materials (the Additional Rights). Amgen may terminate the amended and restated agreement for convenience or due to an uncured material default by us. Our research facility in Huntsville, Alabama that we propose to sell is a different building and location from that of the Facility as described here.

As of June 30, 2012, we have deferred revenue of approximately $41.7 million related to this agreement, which we expect to recognize through October 2020, the estimated end of our obligations under this agreement.

Affymax, Inc.: OMONTYS^®

In April 2004, we entered into a license, manufacturing and supply agreement with Affymax, Inc. (Affymax) under which we provided Affymax with a worldwide, non-exclusive license under certain of our proprietary PEGylation technology to develop, manufacture and commercialize OMONTYS^® (peginesatide). On March 27, 2012, the U.S. Food and Drug Administration (FDA) approved OMONTYS^® to treat anemia in patients with chronic kidney disease on dialysis. Under our agreement, Affymax is obligated to purchase its entire requirements of the proprietary PEGylation materials required to manufacture OMONTYS^® exclusively from Nektar. Affymax is responsible for all clinical development, regulatory and commercialization expenses. We are entitled to royalties based on annual worldwide net sales of OMONTYS^®. For a certain period of time, we will share a portion of our future royalty payments with Enzon Pharmaceuticals, Inc.

In addition, as a result of the FDA’s approval of OMONTYS^®, we earned a $2.0 million milestone payment. Under our milestone method revenue recognition policy, this substantive milestone was recognized in its entirety upon achievement in March 2012. We have previously received other milestone and related payments under our agreement with Affymax and, as of June 30, 2012, we have deferred revenue of approximately $7.5 million, which we expect to recognize through March 2022, the estimated period through which we are required to provide manufacturing and supply services.

Bayer Healthcare LLC: BAY41-6551 (Amikacin Inhale)

In August 2007, we entered into a co-development, license and co-promotion agreement with Bayer Healthcare LLC (Bayer) to develop a specially-formulated inhaled Amikacin. We are responsible for development and manufacturing and supply of the nebulizer device included in the Amikacin product. Bayer is responsible for most future clinical development and commercialization costs, all activities to support worldwide regulatory filings, approvals and related activities, further development of Amikacin Inhale and final product packaging and distribution. We received an upfront payment of $40.0 million in 2007 and performance milestone payments of $20.0 million, of which $10.0 million will be used to reimburse Bayer for Phase 3 clinical trial costs. We are entitled to up to $60.0 million of development milestones upon achievement of certain development objectives, as well as sales milestones upon achievement of annual sales targets and royalties based on annual worldwide net sales of Amikacin Inhale. As of June 30, 2012, we have deferred revenue of approximately $26.0 million related to this agreement, which we expect to recognize through July 2021, the estimated end of our obligations under this agreement.

AstraZeneca AB: NKTR-118 and NKTR-119

In September 2009, we entered into a license agreement with AstraZeneca AB (AstraZeneca), under which we granted AstraZeneca a worldwide, exclusive, perpetual, royalty-bearing, and sublicensable license under our patents and other intellectual property to develop, market, and sell NKTR-118 and NKTR-119. AstraZeneca is responsible for all costs associated with research, development and commercialization and is responsible for all drug development and commercialization decisions for NKTR-118 and NKTR-119. AstraZeneca paid us an upfront payment of $125.0 million, which we received in the fourth quarter of 2009 and which was fully recognized as of December 31, 2010. We are entitled to receive up to $235.0 million and $75.0 million of contingent payments related to NKTR-118 and NKTR-119, respectively, based on development events to be pursued and completed solely by AstraZeneca. In particular, if AstraZeneca files for regulatory approval of NKTR-118 with the FDA and the European Medicines Agency (EMA), Nektar will be entitled to $95.0 million of these payments. We will be entitled to the remaining $140.0 million of these payments if NKTR-118 is approved by the FDA and EMA and commercial launch is achieved in the U.S. and one major country in the European Union. In addition, we are also entitled to sales milestone payments and royalties based on annual worldwide net sales of NTKR-118 and NKTR-119 products. During the three and six months ended June 30, 2012 and 2011, we did not earn significant revenues from this arrangement.

Impairment of Long Lived Assets

6 Months Ended

Jun. 30, 2012

Impairment of Long Lived Assets [Abstract]

Impairment of Long Lived Assets

Note 7 — Impairment of Long Lived Assets

In an effort to reduce ongoing operating costs and improve our organizational structure, efficiency and productivity, in March 2012, we announced a plan to consolidate our U.S.-based research activities at our existing San Francisco location and to cease the use of and sell one of our buildings located in Huntsville, Alabama that was dedicated to research activities. As a result, we performed a preliminary analysis of the fair value of the land, building and related improvements based primarily on available market data. Based upon this analysis, we concluded that the combined carrying value of the land and building exceeded fair value and we recorded an impairment loss of $1.7 million in March 2012. No further impairment losses were recorded in the quarter ended June 30, 2012, however, until we dispose of these assets, we will update our analysis of their fair value on a regular basis and such updates could result in further impairment charges in future periods.

Stock-Based Compensation

6 Months Ended

Jun. 30, 2012

Stock-Based Compensation [Abstract]

Stock-Based Compensation

Note 8 — Stock-Based Compensation

Total stock-based compensation expense was recognized in our Condensed Consolidated Financial Statements as follows (in thousands):


	Three months ended June 30,				Six months ended June 30,
	2012		2011		2012		2011
Cost of goods sold	$	360	$	330	$	768	$	662
Research and development expense		1,703		2,120		3,626		4,089
General and administrative expense		1,738		2,430		3,641		4,931

Total stock-based compensation	$	3,801	$	4,880	$	8,035	$	9,682

During the three months ended June 30, 2012 and 2011, we granted 249,330 and 263,910 stock options, respectively. The weighted average grant-date fair value of options granted during the three months ended June 30, 2012 and 2011 was $4.12 per share and $4.90 per share, respectively.

During the six months ended June 30, 2012 and 2011, we granted 2,982,720 and 2,391,965 stock options, respectively. The weighted average grant-date fair value of options granted during the six months ended June 30, 2012 and 2011 was $3.79 per share and $5.65 per share, respectively.

As a result of stock issuances under our equity compensation plans, during the three months ended June 30, 2012 and 2011, we issued 189,588 and 281,776 common shares, respectively, and during the six months ended June 30, 2012 and 2011, we issued 294,936 and 787,476 common shares, respectively.

- Definition

The entire disclosure for compensation-related costs for equity-based compensation, which may include disclosure of policies, compensation plan details, allocation of equity compensation, incentive distributions, equity-based arrangements to obtain goods and services, deferred compensation arrangements, employee stock ownership plan details and employee stock purchase plan details.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

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-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 14

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-Name Statement of Position (SOP)

-Number 93-6

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+ Details

Net Loss Per Share

6 Months Ended

Jun. 30, 2012

Net Loss Per Share [Abstract]

Net Loss Per Share

Note 9 — Net Loss Per Share

Basic net loss per share is calculated based on the weighted-average number of common shares outstanding during the periods presented. For all periods presented in the accompanying Condensed Consolidated Statements of Operations, the net loss available to common stockholders is equal to the reported net loss. Basic and diluted net loss per share are the same due to our historical net losses and the requirement to exclude potentially dilutive securities which would have an anti-dilutive effect on net loss per share. The weighted average of these potentially dilutive securities has been excluded from the diluted net loss per share calculation and is as follows (in thousands):


	Three months ended June 30,				Six months ended June 30,
	2012		2011		2012		2011
Convertible subordinated notes		9,989		9,989		9,989		9,989
Stock options		14,127		11,620		13,581		11,308

Total		24,116		21,609		23,570		21,297

- Definition

The entire disclosure for earnings per share.

+ References+ Details

Subsequent Event

6 Months Ended

Jun. 30, 2012

Subsequent Event [Abstract]

Subsequent Event

Note 10 — Subsequent Event

On July 11, 2012, we issued $125.0 million in aggregate principal amount of senior secured notes with the entire principal amount due on July 15, 2017, which are secured by a first-priority lien on substantially all of our assets. In connection with this transaction, we retired $42.5 million of principal amount of our convertible subordinated notes in exchange for the same principal amount of senior secured notes. As a result of these transactions, we received cash of $82.5 million, less approximately $4.3 million in transaction costs, of which $25.0 million is required to be maintained in a reserve account until July 1, 2015. The senior secured notes bear interest at 12.0% per annum payable in cash semi-annually in arrears on January 15 and July 15 of each year. We intend to use the proceeds from the issuance of the senior secured notes and our existing cash to repay the remaining $172.5 million in principal amount of our convertible subordinated notes in full at maturity on September 28, 2012.

Organization and Summary of Significant Accounting Policies (Policy)	6 Months Ended
	Jun. 30, 2012
Organization and Summary of Significant Accounting Policies [Abstract]
Organization	*Organization* We are a clinical-stage biopharmaceutical company headquartered in San Francisco, California and incorporated in Delaware. We are developing a pipeline of drug candidates that utilize our PEGylation and advanced polymer conjugate technology platforms with the objective to improve the benefits of drugs for patients. Our research and development activities have required significant resources to date and are expected to continue to require significant resources. As a result, we expect to continue to incur substantial losses and negative cash flows from operations in the future. We have financed our operations primarily through cash from licensing, collaboration and manufacturing agreements and debt and equity financings. At June 30, 2012, we had approximately $477.1 million in cash, cash equivalents, and investments in marketable securities and $239.0 million in indebtedness, including $215.0 million in outstanding convertible subordinated notes due September 28, 2012. On July 11, 2012, we issued $125.0 million in aggregate principal amount of 12.0% senior secured notes due July 2017. We retired $42.5 million in principal amount of the convertible subordinated notes in exchange for the same principal amount of the senior secured notes. We intend to use the proceeds from the issuance of these senior secured notes and our existing cash to repay the remaining $172.5 million in principal amount of the convertible subordinated notes in full at maturity.
Basis of Presentation and Principles of Consolidation	*Basis of Presentation and Principles of Consolidation* Our consolidated financial statements include the financial position, results of operations and cash flows of our wholly-owned subsidiaries: Nektar Therapeutics (India) Private Limited (Nektar India) and Nektar Therapeutics UK Limited. All intercompany accounts and transactions have been eliminated in consolidation. We prepared our Condensed Consolidated Financial Statements following the requirements of the Securities and Exchange Commission (SEC) for interim reporting. As permitted under those rules, certain footnotes or other financial information that are normally required by U.S. generally accepted accounting principles (GAAP) for annual periods can be condensed or omitted. In the opinion of management, these financial statements include all normal and recurring adjustments that we consider necessary for the fair presentation of our financial position and operating results. Our Condensed Consolidated Financial Statements are denominated in U.S. dollars. Accordingly, changes in exchange rates between the applicable foreign currency and the U.S. dollar will affect the translation of each foreign subsidiary’s financial results into U.S. dollars for purposes of reporting our consolidated financial results. Translation gains and losses are included in accumulated other comprehensive loss in the stockholders’ equity section of the Condensed Consolidated Balance Sheets. To date, such cumulative currency translation adjustments have not been material to our consolidated financial position. On January 1, 2012, we were required to adopt new accounting guidance related to the presentation of comprehensive income that prohibits the presentation of other comprehensive income (OCI) in the statement of stockholders’ equity and instead, provides the option of presenting OCI in a continuous statement of comprehensive income or as two separate consecutive statements. Our comprehensive loss consists of our net loss plus our foreign currency translation gains and losses and unrealized holding gains and losses on available-for-sale securities, neither of which were significant during the three and six months ended June 30, 2012 and 2011. This change had no impact on our financial position or results of operations. The accompanying Condensed Consolidated Financial Statements are unaudited. The Condensed Consolidated Balance Sheet data as of December 31, 2011 was derived from the audited consolidated financial statements which are included in our Annual Report on Form 10-K for the year ended December 31, 2011 filed with the SEC on February 29, 2012. The information included in this quarterly report on Form 10-Q should be read in conjunction with the consolidated financial statements and the accompanying notes to those financial statements included in our Annual Report on Form 10-K for the year ended December 31, 2011. Revenue, expenses, assets, and liabilities can vary during each quarter of the year. The results and trends in these interim Condensed Consolidated Financial Statements may not be indicative of the results to be expected for the full year or any other periods.
Use of Estimates	*Use of Estimates* The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. Actual results could differ materially from those estimates. On an ongoing basis, we evaluate our estimates, including those related to deferred revenue recognition periods, inventories, the impairment of investments, the impairment of goodwill and long-lived assets, contingencies, estimated interest expense from our liability related to our sale of future royalties, stock-based compensation, and ongoing litigation, among other estimates. We base our estimates on historical experience and on other assumptions that management believes are reasonable under the circumstances. These estimates form the basis for making judgments about the carrying values of assets and liabilities when these values are not readily apparent from other sources.
Reclassifications	*Reclassifications* Certain items previously reported in specific financial statement captions have been reclassified to conform to the current period presentation. Such reclassifications do not impact previously reported revenue, operating loss or net loss or total assets, liabilities or stockholders’ equity.
Segment Information	*Segment Information* We operate in one business segment which focuses on applying our technology platforms to improve the performance of established and novel drug candidates. We operate in one segment because our business offerings have similar economics and other characteristics, including the nature of products and manufacturing processes, types of customers, distribution methods and regulatory environment. We are comprehensively managed as one business segment by our Chief Executive Officer and his management team.
Significant Concentrations	*Significant Concentrations* Our customers are primarily pharmaceutical and biotechnology companies that are located in the U.S. and Europe. Our accounts receivable balance contains billed and unbilled trade receivables from product sales and royalties, as well as time and materials based billings from collaborative research and development agreements. We provide for an allowance for doubtful accounts by reserving for specifically identified doubtful accounts. We generally do not require collateral from our customers. We perform a regular review of our customers’ payment histories and associated credit risk. We have not experienced significant credit losses from our accounts receivable and our allowance for doubtful accounts was not significant at either June 30, 2012 or December 31, 2011. We are dependent on our suppliers and contract manufacturers to provide raw materials, drugs and devices of appropriate quality and reliability and to meet applicable contract and regulatory requirements. In certain cases, we rely on single sources of supply of one or more critical materials. Consequently, in the event that supplies are delayed or interrupted for any reason, our ability to develop and produce our drug candidates or our ability to meet our supply obligations could be significantly impaired, which could have a material adverse effect on our business, financial condition and results of operations.
Revenue	*Revenue* We enter into arrangements with pharmaceutical and biotechnology partners that may involve multiple deliverables. Our arrangements may contain one or more of the following elements: upfront fees, contract research and development, milestone payments, manufacturing and supply payments, royalties, and license fees. Each deliverable in the arrangement is evaluated to determine whether it meets the criteria to be accounted for as a separate unit of accounting or whether it should be combined with other deliverables. Revenue is recognized separately for each element. On January 1, 2011, we adopted on a prospective basis Accounting Standards Update (ASU) 2009-13, which amends the criteria to identify separate units of accounting within Subtopic 605-25, “Revenue Recognition-Multiple-Element Arrangements.” Under this guidance, at the inception of each new multiple-element arrangement or the material modification of an existing multiple-element arrangement, we allocate all consideration received under multiple-element arrangements to all units of accounting based on the relative selling price method, generally based on our best estimate of selling price (ESP). The objective of ESP is to determine the price at which we would transact a sale if the product or service was sold on a stand-alone basis. We determine ESP for the elements in our collaboration arrangements by considering multiple factors including, but not limited to, technical complexity of the performance obligation and similarity of elements to those performed under previous arrangements. Since we apply significant judgment in arriving at the ESPs, any material change in our estimates would significantly affect the allocation of the total consideration to the different elements of a multiple element arrangement. Product sales and royalties Product sales are primarily derived from cost-plus and fixed price manufacturing and supply agreements with our collaboration partners and revenue is recognized when there is persuasive evidence that an arrangement exists, delivery has occurred, the price is fixed or determinable, and collection is reasonably assured. We have not experienced any significant returns from our customers. Generally, we are entitled to royalties from our partners based on their net sales of approved drugs. We recognize royalty revenue when the cash is received or the royalty amount is otherwise known or when the royalty amount to be received is estimable and collection is reasonably assured. License, collaboration and other Upfront fees received for ongoing obligations, such as manufacturing and supply obligations, under our license and collaborative agreements are recognized ratably over our expected performance period under each respective arrangement. We make our best estimate of the period over which we expect to fulfill our performance obligations, which may include technology transfer assistance, research activities, clinical development activities, and manufacturing activities from development through the commercialization of the product. Given the uncertainties of these collaborative arrangements, significant judgment is required to determine the duration of the performance period. On January 1, 2011, we elected to prospectively adopt ASU 2010-17, “Milestone Method of Revenue Recognition”. Under the milestone method, contingent consideration received from the achievement of a substantive milestone is recognized in its entirety in the period in which the milestone is achieved, which we believe is consistent with the substance of our performance under our various license and collaboration agreements. A milestone is defined as an event (i) that can only be achieved based in whole or in part either on the entity’s performance or on the occurrence of a specific outcome resulting from the entity’s performance, (ii) for which there is substantive uncertainty at the date the arrangement is entered into that the event will be achieved, and (iii) that would result in additional payments being due to the entity. A milestone is substantive if the consideration earned from the achievement of the milestone is consistent with our performance required to achieve the milestone or the increase in value to the collaboration resulting from our performance, relates solely to our past performance, and is reasonable relative to all of the other deliverables and payments within the arrangement. Our license and collaboration agreements with our partners provide for payments to us upon the achievement of development milestones, such as the completion of clinical trials or regulatory submissions, approvals by health authorities, and commercial launches of drug candidates. Given the challenges inherent in developing and obtaining approval for drug products and in achieving commercial launches, there was substantial uncertainty whether any such milestones would be achieved at the time of execution of these licensing and collaboration agreements. In addition, we evaluated whether the development milestones met the remaining criteria to be considered substantive. As a result of our analysis, we consider our development milestones under all of our license and collaboration agreements to be substantive and, accordingly, we expect to recognize as revenue future payments received from such milestones only if and as each milestone is achieved. Our license and collaboration agreements with certain partners also provide for contingent payments to us based solely upon the performance of the respective partner. For such contingent amounts we expect to recognize the payments as revenue when earned under the applicable contract, provided that collection is reasonably assured. Our license and collaboration agreements with our partners also provide for payments to us upon the achievement of specified sales volumes of approved drugs. We consider these payments to be similar to royalty payments and we will recognize such sales-based payments upon achievement of such sales volumes, provided that collection is reasonably assured.
Income Taxes	*Income Taxes* We account for income taxes under the liability method; under this method, deferred tax assets and liabilities are determined based on differences between financial reporting and tax reporting bases of assets and liabilities and are measured using enacted tax rates and laws that are expected to be in effect when the differences are expected to reverse. Realization of deferred tax assets is dependent upon future earnings, the timing and amount of which are uncertain. We record a valuation allowance against deferred tax assets to reduce their carrying value to an amount that is more likely than not to be realized. When we establish or reduce the valuation allowance related to the deferred tax assets, our provision for income taxes will increase or decrease, respectively, in the period such determination is made. For the three and six months ended June 30, 2012 and 2011, we recorded an income tax provision for our Nektar India operations at an effective tax rate of approximately 33% for each period. The U.S. federal deferred tax assets generated from our net operating losses have been fully reserved as we believe it is not more likely than not that the benefit will be realized.

- Definition

Disclosure of accounting policy regarding (1) the principles it follows in consolidating or combining the separate financial statements, including the principles followed in determining the inclusion or exclusion of subsidiaries or other entities in the consolidated or combined financial statements and (2) its treatment of interests (for example, common stock, a partnership interest or other means of exerting influence) in other entities, for example consolidation or use of the equity or cost methods of accounting. The accounting policy may also address the accounting treatment for intercompany accounts and transactions, noncontrolling interest, and the income statement treatment in consolidation for issuances of stock by a subsidiary.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

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- Definition

Disclosure of accounting policy for income taxes, which may include its accounting policies for recognizing and measuring deferred tax assets and liabilities and related valuation allowances, recognizing investment tax credits, operating loss carryforwards, tax credit carryforwards, and other carryforwards, methodologies for determining its effective income tax rate and the characterization of interest and penalties in the financial statements.

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-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32809-109319

Reference 9: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 45

-Paragraph 28

-URI http://asc.fasb.org/extlink&oid=21917399&loc=d3e32280-109318

Reference 10: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 109

-Paragraph 6-34, 43, 47, 49

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 11: http://www.xbrl.org/2003/role/presentationRef

-Publisher AICPA

-Name Accounting Principles Board Opinion (APB)

-Number 4

-Paragraph 11

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

+ Details

- Definition

Disclosure of accounting policy for revenue recognition. If the entity has different policies for different types of revenue transactions, the policy for each material type of transaction is generally disclosed. If a sales transaction has multiple element arrangements (for example, delivery of multiple products, services or the rights to use assets) the disclosure may indicate the accounting policy for each unit of accounting as well as how units of accounting are determined and valued. The disclosure may encompass important judgment as to appropriateness of principles related to recognition of revenue. The disclosure also may indicate the entity's treatment of any unearned or deferred revenue that arises from the transaction.

+ References+ Details

- Definition

Disclosure of accounting policy for the use of estimates in the preparation of financial statements in conformity with generally accepted accounting principles.

+ References+ Details

Cash, Cash Equivalents and Available-For-Sale-Investments (Tables)

6 Months Ended

Jun. 30, 2012

Cash, Cash Equivalents, and Available-For-Sales Investments [Abstract]

Cash, cash equivalents, and available-for-sale investments


	Estimated Fair Value at
	June 30, 2012		December 31, 2011
Cash and cash equivalents	$	136,154	$	15,312
Short-term investments		296,720		225,856
Long-term investments		44,245		173,768

Total cash, cash equivalents, and available-for-sale investments	$	477,119	$	414,936

Portfolio of cash, cash equivalents, and available-for-sale investments


	Estimated Fair Value at
	June 30, 2012		December 31, 2011
Corporate notes and bonds	$	314,473	$	344,427
U.S. corporate commercial paper		19,984		9,464
Obligations of U.S. government agencies		5,003		44,230
Obligations of U.S. states and municipalities		1,505		1,503
Cash and money market funds		136,154		15,312

Total cash, cash equivalents, and available-for-sale investments	$	477,119	$	414,936

portfolio of available-for-sale investments reported as short-term and long-term investments by contractual maturity


	Estimated Fair Value at
	June 30, 2012		December 31, 2011
Less than one year	$	296,720	$	213,386
Greater than one year but less than two years		44,245		186,238

Total available-for-sale investments	$	340,965	$	399,624

Financial assets measured at fair value on a recurring basis


As of June 30, 2012:	Level 1		Level 2		Level 3		Total
Money market funds	$	135,509	$	—	$	—	$	135,509
U.S. corporate commercial paper		—		19,984		—		19,984
Corporate notes and bonds		—		314,473		—		314,473
Obligations of U.S. government agencies		—		5,003		—		5,003
Obligations of U.S. states and municipalities		—		1,505		—		1,505

Cash equivalents and available-for-sale investments	$	135,509	$	340,965	$	—	$	476,474
Cash								645

Cash, cash equivalents, and available-for-sale investments							$	477,119


As of December 31, 2011:	Level 1		Level 2		Level 3		Total
Money market funds	$	13,950	$	—	$	—	$	13,950
U.S. corporate commercial paper		—		9,464		—		9,464
Corporate notes and bonds		—		344,427		—		344,427
Obligations of U.S. government agencies		—		44,230		—		44,230
Obligations of U.S. states and municipalities		—		1,503		—		1,503

Cash equivalents and available-for-sale investments	$	13,950	$	399,624	$	—	$	413,574
Cash								1,362

Cash, cash equivalents, and available-for-sale investments							$	414,936

- Definition

Tabular disclosure of available-for-sale securities which includes, but is not limited to, changes in the cost basis and fair value, fair value and gross unrealized gain (loss), fair values by type of security, contractual maturity and classification, amortized cost basis, contracts to acquire securities to be accounted for as available-for-sale, debt maturities, transfers to trading, change in net unrealized holding gain (loss) net of tax, continuous unrealized loss position fair value, aggregate losses qualitative disclosures, other than temporary impairment (OTTI) losses or other disclosures related to available for sale securities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 7

-URI http://asc.fasb.org/extlink&oid=6872113&loc=d3e27337-111563

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 3

-URI http://asc.fasb.org/extlink&oid=6872113&loc=d3e27198-111563

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 320

-Section 50

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6957658&loc=d3e62557-112803

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 320

-Section 50

-Paragraph 3

-URI http://asc.fasb.org/extlink&oid=6957658&loc=d3e62586-112803

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 2

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-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 9

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-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 6

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 115

-Paragraph 19, 20, 21

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 9: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name FASB Staff Position (FSP)

-Number FAS115-1/124-1

-Paragraph 17

-Subparagraph a, b

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 10: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Emerging Issues Task Force (EITF)

-Number 03-1

-Paragraph 21

-Subparagraph a, b

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

+ Details

- Definition

Tabular disclosure of assets, including [financial] instruments measured at fair value that are classified in stockholders' equity, if any, by class that are measured at fair value on a recurring basis. The disclosures contemplated herein include the fair value measurements at the reporting date by the level within the fair value hierarchy in which the fair value measurements in their entirety fall, segregating fair value measurements using quoted prices in active markets for identical assets (Level 1), significant other observable inputs (Level 2), and significant unobservable inputs (Level 3).

+ References+ Details

Inventory (Tables)

6 Months Ended

Jun. 30, 2012

Inventory [Abstract]

Inventory


	June 30, 2012		December 31, 2011
Raw materials	$	10,181	$	9,754
Work-in-process		2,976		1,219
Finished goods		1,558		1,683

Total	$	14,715	$	12,656

Liability related to sale of future royalties (Tables)

6 Months Ended

Jun. 30, 2012

Summary of liability related to potential future royalties


	Six months ended June 30, 2012
Liability related to sale of future royalties - beginning balance	$	—
Proceeds from sale of future royalties		124,000
Non-cash interest expense		7,155
CIMZIA^® and MIRCERA^® royalties remitted to RPI		(3,469	)

Liability related to sale of future royalties - ending balance	$	127,686

License and Collaboration Agreements (Tables)

6 Months Ended

Jun. 30, 2012

License and Collaboration Agreements [Abstract]

License, collaboration, and other revenue


		Three months ended June 30,				Six months ended June 30,
Partner	Drug or Drug Candidate	2012		2011		2012		2011
Baxter Healthcare	Hemophilia	$	4,369	$	561	$	5,053	$	929
Roche	PEGASYS^® and MIRCERA ^®		1,743		1,283		3,124		2,566
Amgen, Inc.	Neulasta^®		1,250		1,250		2,500		2,500
Affymax, Inc.	Omontys		194		452		2,411		903
Bayer Healthcare LLC	BAY41-6551 (Amikacin Inhale)		799		750		1,543		1,500
Other			1,876		2,027		3,427		4,431

License, collaboration, and other revenue		$	10,231	$	6,323	$	18,058	$	12,829

Stock-Based Compensation (Tables)

6 Months Ended

Jun. 30, 2012

Stock-Based Compensation [Abstract]

Total stock-based compensation expense


	Three months ended June 30,				Six months ended June 30,
	2012		2011		2012		2011
Cost of goods sold	$	360	$	330	$	768	$	662
Research and development expense		1,703		2,120		3,626		4,089
General and administrative expense		1,738		2,430		3,641		4,931

Total stock-based compensation	$	3,801	$	4,880	$	8,035	$	9,682

- Definition

Tabular disclosure of the allocation of equity-based compensation costs to a given line item on the balance sheet and income statement for the period. This may include the reporting line for the costs and the amount capitalized and expensed.

+ References+ Details

Net Loss Per Share (Tables)

6 Months Ended

Jun. 30, 2012

Net Loss Per Share [Abstract]

Net Loss Per Share


	Three months ended June 30,				Six months ended June 30,
	2012		2011		2012		2011
Convertible subordinated notes		9,989		9,989		9,989		9,989
Stock options		14,127		11,620		13,581		11,308

Total		24,116		21,609		23,570		21,297

Organization and Summary of Significant Accounting Policies (Details) (USD $)	3 Months Ended		6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012 Segment	Jun. 30, 2011	Jul. 11, 2012	Dec. 31, 2011	Jul. 15, 2017 Senior Notes [Member]
Organization and Summary of Significant Accounting Policies [Line Items]
Senior secured notes, interest rate							12.00%
Organization and Summary of Significant Accounting Policies (Textual) [Abstract]
Cash, cash equivalents, and investments in marketable securities	$ 477,100,000		$ 477,100,000
Indebtedness	239,000,000		239,000,000
Outstanding convertible subordinated notes	214,955,000		214,955,000			214,955,000
Senior secured notes, issued					125,000,000
Allowance for doubtful accounts	0		0			0
Principal amount of the convertible subordinated notes , retired amount					42,500,000
Convertible subordinated notes remaining					$ 172,500,000
Effective income tax rate	33.00%	33.00%	33.00%	33.00%
Number of business segments			1

Cash, Cash Equivalents, and Available-For-Sale Investments (Details) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2012	Dec. 31, 2011	Jun. 30, 2011	Dec. 31, 2010
Cash, cash equivalents, and available-for-sale investments
Cash and cash equivalents	$ 136,154	$ 15,312	$ 11,626	$ 17,755
Short-term investments	296,720	225,856
Long-term investments	44,245	173,768
Total cash, cash equivalents, and available-for-sale investments	$ 477,119	$ 414,936

- Definition

Amount of investment in debt and equity securities categorized neither as trading securities nor held-to-maturity securities and intended be sold or mature one year or operating cycle, if longer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 25

-Paragraph 1

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=7534914&loc=d3e22054-111558

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 115

-Paragraph 12

-Subparagraph b

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 115

-Paragraph 16

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 133

-Paragraph 22

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 5: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name FASB Staff Position (FSP)

-Number FAS115-1/124-1

-Paragraph 15D

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 6: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 45

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6871852&loc=d3e26626-111562

Reference 7: http://www.xbrl.org/2003/role/presentationRef

-Publisher AICPA

-Name Accounting Research Bulletin (ARB)

-Number 43

-Section A

-Paragraph 4, 5

-Chapter 3

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 8: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 115

-Paragraph 13, 17

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 9: http://www.xbrl.org/2003/role/presentationRef

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-Name FASB Staff Position (FSP)

-Number FAS115-1/124-1

-Paragraph 15C

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

+ Details

- Definition

Investments in debt and equity securities which are categorized neither as held-to-maturity nor trading and which are intended to be sold or mature more than one year from the balance sheet date or operating cycle, if longer. Such securities are reported at fair value; unrealized gains (losses) related to Available-for-sale Securities are excluded from earnings and reported in a separate component of shareholders' equity (other comprehensive income), unless the Available-for-sale security is designated as a hedge or is determined to have had an other than temporary decline in fair value below its amortized cost basis. All or a portion of the unrealized holding gain (loss) of an Available-for-sale security that is designated as being hedged in a fair value hedge is recognized in earnings during the period of the hedge, as are other than temporary declines in fair value below the cost basis for investments in equity securities and debt securities that an entity intends to sell or it is more likely than not that it will be required to sell before the recovery of its amortized cost basis. Other than temporary declines in fair value below the cost basis for debt securities categorized as Available-for-sale that an entity does not intend to sell and for which it is not more likely than not that the entity will be required to sell before the recovery of its amortized cost basis are bifurcated into credit losses and losses related to all other factors. Other than temporary declines in fair value below cost basis related to credit losses are recognized in earnings, and losses related to all other factors are recognized in other comprehensive income.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 115

-Paragraph 12

-Subparagraph b

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name FASB Staff Position (FSP)

-Number FAS115-1/124-1

-Paragraph 15D

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 45

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6871852&loc=d3e26626-111562

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-Publisher FASB

-Name FASB Staff Position (FSP)

-Number FAS115-1/124-1

-Paragraph 15E

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 5: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name FASB Staff Position (FSP)

-Number FAS115-1/124-1

-Paragraph 15C

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 6: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Available-for-Sale Securities

-URI http://asc.fasb.org/extlink&oid=6505594

Reference 7: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 115

-Paragraph 17

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

+ Details

- Definition

Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Cash

-URI http://asc.fasb.org/extlink&oid=6506951

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Cash Equivalents

-URI http://asc.fasb.org/extlink&oid=6507016

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 95

-Paragraph 8, 9

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.1)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 5: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 95

-Paragraph 7

-Footnote 1

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 6: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 1

-Article 5

Reference 7: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section 45

-Paragraph 1

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=6361293&loc=d3e6676-107765

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 4

-URI http://asc.fasb.org/extlink&oid=6943989&loc=d3e3044-108585

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 95

-Paragraph 7, 26

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

+ Details

Cash, Cash Equivalents, and Available-For-Sale Investments (Details 1) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2012	Dec. 31, 2011	Jun. 30, 2011	Dec. 31, 2010
Schedule of Available-for-sale Securities [Line Items]
Cash and money market funds	$ 136,154	$ 15,312	$ 11,626	$ 17,755
Cash, cash equivalents, and available-for-sale investments	477,119	414,936
Corporate notes and bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale securities, fair value	314,473	344,427
U.S. corporate commercial paper [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale securities, fair value	19,984	9,464
Obligations of U.S. government agencies [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale securities, fair value	5,003	44,230
Obligations of U.S. states and municipalities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale securities, fair value	$ 1,505	$ 1,503

- Definition

This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents Available-for-sale Securities which consist of all investments in certain debt and equity securities neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities which are categorized as Available-for-sale.

+ References+ Details

- Definition

+ References

+ Details

Cash, Cash Equivalents, and Available-For-Sale Investments (Details 2) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2012	Dec. 31, 2011
Portfolio of available-for-sale investments
Less than one year	$ 296,720	$ 213,386
Greater than one year but less than two years	44,245	186,238
Total available-for-sale investments	$ 340,965	$ 399,624

- Definition

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 25

-Paragraph 1

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=7534914&loc=d3e22054-111558

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 115

-Paragraph 12

-Subparagraph b

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 115

-Paragraph 16

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 115

-Paragraph 14

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 5: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 115

-Paragraph 13

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 6: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 133

-Paragraph 22

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 7: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name FASB Staff Position (FSP)

-Number FAS115-1/124-1

-Paragraph 15D

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 8: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name FASB Staff Position (FSP)

-Number FAS115-1/124-1

-Paragraph 15E

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 9: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name FASB Staff Position (FSP)

-Number FAS115-1/124-1

-Paragraph 15C

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 10: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6871852&loc=d3e26610-111562

+ Details

Cash, Cash Equivalents, and Available-For-Sale Investments (Details 3) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2012	Dec. 31, 2011
Fair value assets measured on recurring basis
Cash, cash equivalents, and available-for-sale investments	$ 477,119	$ 414,936
U.S. corporate commercial paper [Member]
Fair value assets measured on recurring basis
Available-for-sale securities, fair value	19,984	9,464
Corporate notes and bonds [Member]
Fair value assets measured on recurring basis
Available-for-sale securities, fair value	314,473	344,427
Obligations of U.S. government agencies [Member]
Fair value assets measured on recurring basis
Available-for-sale securities, fair value	5,003	44,230
Obligations of U.S. states and municipalities [Member]
Fair value assets measured on recurring basis
Available-for-sale securities, fair value	1,505	1,503
Recurring [Member]
Fair value assets measured on recurring basis
Money market funds	135,509	13,950
Cash equivalents and available-for-sale investments, fair value	476,474	413,574
Cash	645	1,362
Cash, cash equivalents, and available-for-sale investments	477,119	414,936
Recurring [Member] \| Level 1 [Member]
Fair value assets measured on recurring basis
Money market funds	135,509	13,950
Cash equivalents and available-for-sale investments, fair value	135,509	13,950
Recurring [Member] \| Level 2 [Member]
Fair value assets measured on recurring basis
Cash equivalents and available-for-sale investments, fair value	340,965	399,624
Recurring [Member] \| Level 3 [Member]
Fair value assets measured on recurring basis
Money market funds
Cash equivalents and available-for-sale investments, fair value
Recurring [Member] \| U.S. corporate commercial paper [Member]
Fair value assets measured on recurring basis
Available-for-sale securities, fair value	19,984	9,464
Recurring [Member] \| U.S. corporate commercial paper [Member] \| Level 2 [Member]
Fair value assets measured on recurring basis
Available-for-sale securities, fair value	19,984	9,464
Recurring [Member] \| U.S. corporate commercial paper [Member] \| Level 3 [Member]
Fair value assets measured on recurring basis
Available-for-sale securities, fair value
Recurring [Member] \| Corporate notes and bonds [Member]
Fair value assets measured on recurring basis
Available-for-sale securities, fair value	314,473	344,427
Recurring [Member] \| Corporate notes and bonds [Member] \| Level 2 [Member]
Fair value assets measured on recurring basis
Available-for-sale securities, fair value	314,473	344,427
Recurring [Member] \| Corporate notes and bonds [Member] \| Level 3 [Member]
Fair value assets measured on recurring basis
Available-for-sale securities, fair value
Recurring [Member] \| Obligations of U.S. government agencies [Member]
Fair value assets measured on recurring basis
Available-for-sale securities, fair value	5,003	44,230
Recurring [Member] \| Obligations of U.S. government agencies [Member] \| Level 2 [Member]
Fair value assets measured on recurring basis
Available-for-sale securities, fair value	5,003	44,230
Recurring [Member] \| Obligations of U.S. government agencies [Member] \| Level 3 [Member]
Fair value assets measured on recurring basis
Available-for-sale securities, fair value
Recurring [Member] \| Obligations of U.S. states and municipalities [Member]
Fair value assets measured on recurring basis
Available-for-sale securities, fair value	1,505	1,503
Recurring [Member] \| Obligations of U.S. states and municipalities [Member] \| Level 2 [Member]
Fair value assets measured on recurring basis
Available-for-sale securities, fair value	1,505	1,503
Recurring [Member] \| Obligations of U.S. states and municipalities [Member] \| Level 3 [Member]
Fair value assets measured on recurring basis
Available-for-sale securities, fair value

- Definition

+ References+ Details

- Definition

+ References+ Details

- Definition

This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item includes currency on hand as well as demand deposits with banks or financial institutions. It also includes other kinds of accounts that have the general characteristics of demand deposits in that the Company may deposit additional funds at any time and also effectively may withdraw funds at any time without prior notice or penalty. Cash equivalents, excluding items classified as marketable securities, include short-term, highly liquid investments that are both readily convertible to known amounts of cash, and so near their maturity that they present minimal risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify under that definition. Original maturity means original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three years ago does not become a cash equivalent when its remaining maturity is three months.

+ References+ Details

Cash, Cash Equivalents, and Available-For-Sale Investments (Details Textual) (USD $) In Millions, unless otherwise specified	6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011
Cash Cash Equivalents and Available for Sale Investments (Textual) [Abstract]
Weighted average maturity term for debt securities investment	one year or less
Available-for-sale securities, sold	$ 0	$ 180.5
Accounting treatment for short-term securities	Investments in securities with remaining maturities of less than one year, or where our intent is to use the investments to fund current operations, or to make them available for current operations, are classified as short-term investments.
Maximum maturity term for debt securities investment	two years or less

- Definition

An element designated to encapsulate any additional information related to cash and cash equivalents not otherwise addressed by the existing taxonomy. Cash includes currency on hand as well as demand deposits with banks or financial institutions. It also includes other kinds of accounts that have the general characteristics of demand deposits in that the Entity may deposit additional funds at any time and also effectively may withdraw funds at any time without prior notice or penalty. Cash equivalents, excluding items classified as marketable securities, include short-term, highly liquid investments that are both readily convertible to known amounts of cash, and so near their maturity that they present minimal risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify under that definition. Original maturity means original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three years ago does not become a cash equivalent when its remaining maturity is three months.

+ References+ Details

Inventory (Details) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2012	Dec. 31, 2011
Inventory
Raw materials	$ 10,181	$ 9,754
Work-in-process	2,976	1,219
Finished goods	1,558	1,683
Total	$ 14,715	$ 12,656

Liability related to sale of future royalties (Details) (USD $) In Thousands, unless otherwise specified	6 Months Ended
	Jun. 30, 2012
Summary of liability related to potential future royalties
Liability related to sale of future royalties - beginning balance
Proceeds from sale of potential future royalties	124,000
Non-cash interest expense	7,155
Royalties remitted to purchaser	(3,469)
Ending balance	$ 127,686

Liability related to sale of future royalties (Details Textual) (USD $)			6 Months Ended	3 Months Ended		6 Months Ended	3 Months Ended	12 Months Ended	3 Months Ended	12 Months Ended
	Jun. 30, 2012	Dec. 31, 2011	Jun. 30, 2012 Purchase and Sale Agreement with RPI [Member]	Jun. 30, 2012 CIMZIA and MIRCERA [Member]	Mar. 31, 2012 CIMZIA and MIRCERA [Member]	Jun. 30, 2012 CIMZIA and MIRCERA [Member]	Jun. 30, 2012 Milestone Scenario One [Member]	Dec. 31, 2012 Milestone Scenario One [Member]	Jun. 30, 2012 Milestone Scenario Two [Member]	Dec. 31, 2013 Milestone Scenario Two [Member]
Liability Related to Sale of Future Royalties (Textual) [Abstract]
Proceeds from sale of royalty rights			$ 124,000,000
Transaction costs related to sale of potential future royalties			4,400,000
Potential payments milestone not achieved year one								3,000,000
Potential payments milestone not achieved year two										7,000,000
Liability related to sale of future royalties	127,686,000
Royalty agreement contingent payment description							if certain worldwide net sales thresholds of MIRCERA® for the 12 month period ending on December 31, 2012 are not achieved		if certain worldwide net sales thresholds of MIRCERA® for the 12 month period ending on December 31, 2013 are not achieved
Royalty revenues				$ 3,500,000	$ 2,700,000	$ 6,200,000
Effective interest rate under royalty agreement	0.17

License and Collaboration Agreements (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011
License, collaboration, and other revenue
License, collaboration and other revenue	$ 10,231	$ 6,323	$ 18,058	$ 12,829
Roche [Member] \| Pegasys And Mircera [Member]
License, collaboration, and other revenue
License, collaboration and other revenue	1,743	1,283	3,124	2,566
Baxter Healthcare [Member] \| Hemophilia [Member]
License, collaboration, and other revenue
License, collaboration and other revenue	4,369	561	5,053	929
Affymax Inc [Member] \| Omontys [Member]
License, collaboration, and other revenue
License, collaboration and other revenue	194	452	2,411	903
Amgen Inc [Member] \| Neulasta [Member]
License, collaboration, and other revenue
License, collaboration and other revenue	1,250	1,250	2,500	2,500
Bayer Healthcare LLC [Member] \| BAY41-6551 (Amikacin Inhale) [Member]
License, collaboration, and other revenue
License, collaboration and other revenue	799	750	1,543	1,500
Other [Member]
License, collaboration, and other revenue
License, collaboration and other revenue	$ 1,876	$ 2,027	$ 3,427	$ 4,431

License and Collaboration Agreements (Details Textual) (USD $) In Millions, unless otherwise specified		6 Months Ended	2 Months Ended	3 Months Ended			6 Months Ended	12 Months Ended		6 Months Ended	12 Months Ended	3 Months Ended	6 Months Ended	2 Months Ended	6 Months Ended	1 Months Ended	6 Months Ended					6 Months Ended
	Jun. 30, 2012	Jun. 30, 2012 Roche [Member] Performance milestone payments [Member]	Dec. 31, 2009 Roche [Member] License Option [Member]	Dec. 31, 2010 Amgen Inc [Member]	Jun. 30, 2012 Amgen Inc [Member]	Jun. 30, 2012 AstraZeneca AB [Member]	Jun. 30, 2012 Bayer Healthcare LLC [Member]	Dec. 31, 2007 Bayer Healthcare LLC [Member] Up-front Payment Arrangement [Member]	Dec. 31, 2007 Bayer Healthcare LLC [Member] Performance milestone payments [Member]	Jun. 30, 2012 Baxter Healthcare [Member]	Dec. 31, 2005 Baxter Healthcare [Member]	Dec. 31, 2009 NKTR-118 and NKTR-119 [Member] AstraZeneca AB [Member] Up-front Payment Arrangement [Member]	Jun. 30, 2012 MIRCERA [Member] Roche [Member]	Feb. 29, 2012 MIRCERA [Member] Roche [Member] Up-front Payment Arrangement [Member]	Jun. 30, 2012 MIRCERA [Member] Roche [Member] Up-front Payment Arrangement [Member]	Feb. 29, 2012 MIRCERA [Member] Roche [Member] Performance milestone payments [Member]	Jun. 30, 2012 MIRCERA [Member] Roche [Member] Performance milestone payments [Member]	Jun. 30, 2012 NKTR-118 [Member]	Jun. 30, 2012 NKTR-118 [Member] AstraZeneca AB [Member]	Jun. 30, 2012 NKTR-119 [Member] AstraZeneca AB [Member]	Jun. 30, 2012 Hemophilia [Member] Baxter Healthcare [Member]	Jun. 30, 2012 Hemophilia B [Member]	Jun. 30, 2012 Omontys [Member] Affymax Inc [Member]	Mar. 27, 2012 Omontys [Member] Affymax Inc [Member]	Jun. 30, 2012 PEGASYS [Member] Roche [Member]
License and Collaboration Agreements (Textual) [Abstract]
Potential future payments for development milestones	$ 161.1						$ 60.0														$ 28.0
Substantive milestone revenue																								2.0
Deferred Revenue					41.7		26.0						14.4								1.5		7.5		18.0
Received upfront and milestone payments			31.0	50.0				40.0	20.0	5.0	4.0	125.0		5.0	10.0		6.0
Revenue recognized as contractual obligations completed													1.6									3.9
Contingent payments receivable based on development events to be pursued and completed solely by others						95.0												140.0	235.0	75.0
Performance milestone to be used to reimburse future clinical trial costs							10.0
Expected consideration		11.0											27.0			22.0
Revenue from product sales													$ 1.1

Impairment of Long Lived Assets (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended	6 Months Ended
	Mar. 31, 2012	Jun. 30, 2012
Impairment of Long Lived Assets (Textual) [Abstract]
Impairment of long-lived assets	$ 1,675	$ 1,675

- Definition

The aggregate amount of write-downs for impairments recognized during the period for long lived assets held for use (including those held for disposal by means other than sale).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6943989&loc=d3e3602-108585

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 360

-SubTopic 10

-Section 45

-Paragraph 4

-URI http://asc.fasb.org/extlink&oid=8077374&loc=d3e2420-110228

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 360

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6391110&loc=d3e2921-110230

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 144

-Paragraph 26

-Subparagraph b

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 5: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 958

-SubTopic 225

-Section 45

-Paragraph 11

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=6743430&loc=d3e92212-112881

Reference 6: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Impairment

-URI http://asc.fasb.org/extlink&oid=6515133

Reference 7: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 144

-Paragraph 7, 25

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

+ Details

Stock-Based Compensation (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011
Total stock-based compensation expense
Total stock-based compensation cost	$ 3,801	$ 4,880	$ 8,035	$ 9,682
Cost of goods sold [Member]
Total stock-based compensation expense
Total stock-based compensation cost	360	330	768	662
Research and development expense [Member]
Total stock-based compensation expense
Total stock-based compensation cost	1,703	2,120	3,626	4,089
General and administrative expense [Member]
Total stock-based compensation expense
Total stock-based compensation cost	$ 1,738	$ 2,430	$ 3,641	$ 4,931

- Definition

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

+ References+ Details

Stock-Based Compensation (Details Textual) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011
Stock options [Member]
Stock Based Compensation (Textual) [Abstract]
Granted stock options	249,330	263,910	2,982,720	2,391,965
Weighted-average grant-date fair value	$ 4.12	$ 4.90	$ 3.79	$ 5.65
Common Shares [Member]
Stock Based Compensation (Textual) [Abstract]
Stock issuances under equity compensation plans	189,588	281,776	294,936	787,476

- Definition

Number of shares (or other type of equity) issued during the period as a result of any equity-based compensation plan other than an employee stock ownership plan (ESOP), net of any shares forfeited. Shares issued could result from the issuance of restricted stock, the exercise of stock options, stock issued under employee stock purchase plans, and/or other employee benefit plans.

+ References+ Details

Net Loss Per Share (Details) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011
Antidilutive securities excluded from computation of earning per share
Total	24,116	21,609	23,570	21,297
Convertible subordinated notes [Member]
Antidilutive securities excluded from computation of earning per share
Total	9,989	9,989	9,989	9,989
Stock options [Member]
Antidilutive securities excluded from computation of earning per share
Total	14,127	11,620	13,581	11,308

- Definition

Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Antidilution

-URI http://asc.fasb.org/extlink&oid=6505113

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Diluted Earnings Per Share

-URI http://asc.fasb.org/extlink&oid=6510752

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Contingent Stock Agreement

-URI http://asc.fasb.org/extlink&oid=6508534

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 260

-SubTopic 10

-Section 50

-Paragraph 1

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257

Reference 5: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 128

-Paragraph 40

-Subparagraph c

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 6: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 128

-Paragraph 13, 14

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 7: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Emerging Issues Task Force (EITF)

-Number 07-4

-Paragraph 4

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 8: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 128

-Paragraph 171

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

+ Details

Subsequent Event (Details) (USD $) In Millions, unless otherwise specified	1 Months Ended	6 Months Ended
	Jul. 31, 2012	Jun. 30, 2012	Jul. 11, 2012
Subsequent Event (Textual) [Abstract]
Senior secured notes, issued			$ 125.0
Total cash receivables of senior secured notes	82.5
Convertible subordinated notes remaining			172.5
Amount Reserved			25.0
Issuance of Debt [Member]
Subsequent Event (Textual) [Abstract]
Senior secured notes, issued			125.0
Maturity date of Senior secured notes	Jul. 15, 2017
Retirement of convertible subordinated notes	42.5
Issuance costs	$ 4.3
Interest rate			12.00%
Maturity date of convertible subordinated notes		Sep. 28, 2012