Exelixis (EXEL) 10-Q 1 May 14 2014 Q1 Quarterly report Financial data

Document_And_Entity_Informatio

Document And Entity Information	3 Months Ended
	Mar. 31, 2014	Apr. 24, 2014
Document And Entity Information [Abstract]	'	'
Document Type	'10-Q	'
Amendment Flag	'false	'
Document Period End Date	28-Mar-14	'
Document Fiscal Year Focus	'2014	'
Document Fiscal Period Focus	'Q1	'
Trading Symbol	'exel	'
Entity Registrant Name	'EXELIXIS, INC.	'
Entity Central Index Key	'0000939767	'
Entity Filer Category	'Large Accelerated Filer	'
Current Fiscal Year End Date	'--01-02	'
Entity Common Stock, Shares Outstanding	'	194,694,949

Condensed_Consolidated_Balance

Condensed Consolidated Balance Sheets (USD $)	Mar. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Current assets:	'	'
Cash and cash equivalents	$157,539	$103,978	[1]
Short-term investments	116,033	138,475	[1]
Short-term restricted cash and investments	12,208	12,213	[1]
Trade and other receivables	4,457	3,941	[1]
Inventory	2,686	2,890	[1]
Prepaid expenses and other current assets	5,386	5,112	[1]
Total current assets	298,309	266,609	[1]
Long-term investments	111,155	144,299	[1]
Long-term restricted cash and investments	10,814	16,897	[1]
Property and equipment, net	4,685	4,910	[1]
Goodwill	63,684	63,684	[1]
Other assets	8,918	6,888	[1]
Total assets	497,565	503,287	[1]
Current liabilities:	'	'
Accounts payable	4,943	9,345	[1]
Accrued clinical trial liabilities	39,118	34,958	[1]
Accrued compensation and benefits	8,088	12,797	[1]
Other accrued liabilities	11,974	13,116	[1]
Current portion of convertible notes	0	10,000	[1]
Current portion of loans payable	1,392	1,762	[1]
Current portion of restructuring	4,298	4,425	[1]
Deferred revenue	1,243	1,450	[1]
Total current liabilities	71,056	87,853	[1]
Long-term portion of convertible notes	261,408	255,147	[1]
Long-term portion of loans payable	80,219	80,328	[1]
Long-term portion of restructuring	7,933	9,047	[1]
Other long-term liabilities	5,467	4,674	[1]
Total liabilities	426,083	437,049	[1]
Commitments	'	'	[1]
Stockholders' Equity:	'	'
Preferred stock	0	0	[1]
Common stock, $0.001 par value; 400,000,000 shares authorized; issued and outstanding: 194,652,943 and 184,533,651 shares at March 31, 2014 and December 31, 2013, respectively	194	184	[1]
Additional paid-in capital	1,644,516	1,564,670	[1]
Accumulated other comprehensive income	153	146	[1]
Accumulated deficit	-1,573,381	-1,498,762	[1]
Total stockholders’ equity	71,482	66,238	[1]
Total liabilities and stockholders' equity	$497,565	$503,287	[1]
[1]	The condensed consolidated balance sheet as of December 31, 2013 has been derived from the audited financial statements as of that date.

Condensed_Consolidated_Balance1

Condensed Consolidated Balance Sheets (Parenthetical) (USD $)	Mar. 31, 2014	Dec. 31, 2013
Statement of Financial Position [Abstract]	'	'
Common stock, par value, in dollars per share	$0.00	$0.00
Common stock, shares authorized	400,000,000	400,000,000
Common stock, shares issued	194,652,943	184,533,651
Common stock, shares outstanding	194,652,943	184,533,651

Condensed_Consolidated_Stateme

Condensed Consolidated Statements Of Operations (USD $)	3 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013
Revenues:	'	'
Net product revenues	$4,905	$1,856
License and contract revenues	0	7,813
Total revenues	4,905	9,669
Operating expenses:	'	'
Cost of goods sold	309	280
Research and development	54,847	32,735
Selling, general and administrative	14,691	10,545
Restructuring charge	46	119
Total operating expenses	69,893	43,679
Loss from operations	-64,988	-34,010
Other income (expense), net:	'	'
Interest income and other, net	2,131	338
Interest expense	-11,762	-11,057
Total other income (expense), net	-9,631	-10,719
Net loss	($74,619)	($44,729)
Net loss per share, basic and diluted, in dollars per share	($0.39)	($0.24)
Shares used in computing basic and diluted net loss per share, in shares	191,699	183,742

Condensed_Consolidated_Stateme1

Condensed Consolidated Statements of Comprehensive Loss (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2014		Mar. 31, 2013
Statement of Comprehensive Income [Abstract]	'		'
Net loss	($74,619)		($44,729)
Other comprehensive income	7	[1]	194	[1]
Comprehensive loss	($74,612)		($44,535)
[1]	Other comprehensive income consisted solely of unrealized gains or losses, net on available for sale securities arising during the periods presented. There were no reclassification adjustments to net loss resulting from realized gains or losses on the sale of securities and there was no income tax expense related to other comprehensive income during those periods.

Condensed_Consolidated_Stateme2

Condensed Consolidated Statements of Cash Flows (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2014		Mar. 31, 2013
Cash flows from operating activities:	'		'
Net loss	($74,619)		($44,729)
Adjustments to reconcile net loss to net cash used in operating activities:	'		'
Depreciation and amortization	498		842
Stock-based compensation expense	3,758		2,679
Accretion of debt discount	6,988		6,314
Gain on warrants	-1,739		0
Other	1,475		1,733
Changes in assets and liabilities:	'		'
Trade and other receivables	-516		-1,114
Inventory	204		-280
Prepaid expenses and other current assets	-359		-4,757
Other assets	-5		0
Accounts payable, accrued compensation, and other accrued liabilities	-10,254		-4,769
Clinical trial liabilities	4,160		-703
Restructuring liability	-1,241		-2,378
Other long-term liabilities	-229		-143
Deferred revenue	-207		-7,110
Net cash used in operating activities	-72,086		-54,415
Cash flows from investing activities:	'		'
Purchases of property and equipment	-384		-729
Proceeds from sale of property and equipment	276		0
Proceeds from maturities of restricted cash and investments	6,598		6,647
Purchase of restricted cash and investments	-504		-504
Proceeds from maturities of investments	90,311		157,096
Purchases of investments	-35,937		-96,157
Net cash provided by investing activities	60,360		66,353
Cash flows from financing activities:	'		'
Proceeds from issuance of common stock, net	75,646		0
Proceeds from exercise of stock options and warrants	120		16
Principal payments on debt	-10,479		-10,791
Net cash provided by (used in) financing activities	65,287		-10,775
Net increase in cash and cash equivalents	53,561		1,163
Cash and cash equivalents at beginning of period	103,978	[1]	170,069
Cash and cash equivalents at end of period	157,539		171,232
Supplemental cash flow disclosure - non-cash financing activity:	'		'
Issuance of warrants in connection with amendment to convertible notes	$2,762		$0
[1]	The condensed consolidated balance sheet as of December 31, 2013 has been derived from the audited financial statements as of that date.

Organization_and_Summary_of_Si

Organization and Summary of Significant Accounting Policies	3 Months Ended
	Mar. 31, 2014
Organization, Consolidation and Presentation of Financial Statements [Abstract]	'
Organization and Summary of Significant Accounting Policies	'
	ORGANIZATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
	Organization
	Exelixis, Inc. (“Exelixis,” “we,” “our” or “us”) is a biopharmaceutical company committed to developing small molecule therapies for the treatment of cancer. Our two most advanced assets, COMETRIQ® (cabozantinib), our wholly-owned inhibitor of multiple receptor tyrosine kinases, and cobimetinib (GDC-0973/XL518), a potent, highly selective inhibitor of MEK, which we out-licensed to Genentech, Inc. (a member of the Roche Group) (“Genentech”), are currently the subject of six ongoing phase 3 pivotal trials.
	We are focusing our development and commercialization efforts primarily on COMETRIQ (cabozantinib), which was approved by the U.S. Food and Drug Administration (“FDA”) on November 29, 2012, for the treatment of progressive, metastatic medullary thyroid cancer (“MTC”) in the United States, where it became commercially available in late January 2013. In March 2014, the European Commission approved COMETRIQ for the treatment of adult patients with progressive, unresectable locally advanced or metastatic MTC. The European Commission granted conditional marketing authorization following a positive opinion from the European Committee for Medicinal Products for Human Use (“CHMP”) issued in December 2013.
	Basis of Consolidation
	The consolidated financial statements include the accounts of Exelixis and those of our wholly-owned subsidiaries. These entities’ functional currency is the U.S. dollar. All intercompany balances and transactions have been eliminated.
	Basis of Presentation
	The accompanying unaudited consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States for interim financial information and pursuant to Form 10-Q and Article 10 of Regulation S-X of the Securities and Exchange Commission (“SEC”). Accordingly, they do not include all of the information and footnotes required by U.S. generally accepted accounting principles for complete financial statements. In our opinion, all adjustments (consisting only of normal recurring adjustments) considered necessary for a fair presentation of the results of operations and cash flows for the period presented have been included.
	Exelixis adopted a 52- or 53-week fiscal year that generally ends on the Friday closest to December 31st. Fiscal year 2013, a 52-week year, ended on December 27, 2013, and fiscal year 2014, a 53-week year, will end on January 2, 2015. For convenience, references in this report as of and for the fiscal quarters ended March 29, 2013 and March 28, 2014, and as of the fiscal year ended December 27, 2013, are indicated as ended March 31, 2013, March 31, 2014, and December 31, 2013, respectively.
	Operating results for the three months ended March 31, 2014 are not necessarily indicative of the results that may be expected for the fiscal year ending January 2, 2015 or for any future period. These financial statements and notes should be read in conjunction with the consolidated financial statements and notes thereto for the year ended December 31, 2013, included in our Annual Report on Form 10-K filed with the SEC on February 20, 2014.
	Segment Information
	We operate as a single reportable segment.
	Use of Estimates
	The preparation of our consolidated financial statements is in conformity with accounting principles generally accepted in the United States which requires management to make judgments, estimates and assumptions that affect the reported amounts of assets, liabilities, revenue and expenses, and related disclosures. On an ongoing basis, management evaluates its estimates including, but not limited to, those related to inventory, revenue recognition, valuation of long-lived assets, certain accrued liabilities including clinical trial accruals and restructuring liability, valuation of warrants, share-based compensation and the valuation of the debt and equity components of our convertible debt at issuance. We base our estimates on historical experience and on various other market-specific and other relevant assumptions that we believe to be reasonable under the circumstances, the results of which form the basis for making judgments about the carrying values of assets and liabilities that are not readily apparent from other sources. Actual results could differ materially from those estimates.
	Revenue Recognition
	We recognize revenue from the sale of COMETRIQ and from license fees and milestones earned on research and collaboration arrangements. See “Note 1 - Organization and Summary of Significant Accounting Policies” to our Consolidated Financial Statements included in our Annual Report on Form 10-K for the year ended December 31, 2013 for a description of our policies for revenue recognition on research and collaboration agreements. We did not enter into any new collaboration agreements during the three months ended March 31, 2014. See “Note 2 - Research and Collaboration Agreements” to our Consolidated Financial Statements included in our Annual Report on Form 10-K for the year ended December 31, 2013 for a description of our existing collaboration agreements.
	Net Product Revenues
	We recognize revenue when it is both realized or realizable and earned, meaning persuasive evidence of an arrangement exists, delivery has occurred, title has transferred, the price is fixed or determinable, there are no remaining customer acceptance requirements, and collectability of the resulting receivable is reasonably assured. For product sales in the United States, this generally occurs upon shipment of the product to the patient by our distributor. For product sales in Europe, this occurs when our European distribution partner has accepted the product.
	We sell our product, COMETRIQ, in the United States to a specialty pharmacy that benefits from customer incentives and has a right of return. We have a limited sales history and cannot reliably estimate expected returns of the product nor the discounts and rebates due to payors at the time of shipment to the specialty pharmacy. Accordingly, upon shipment to the specialty pharmacy, we record deferred revenue on our Consolidated Balance Sheets. We recognize revenue when the specialty pharmacy provides the product to a patient based on the fulfillment of a prescription. We record revenue using an analysis of prescription data from our specialty pharmacy to ascertain the date of shipment and the payor mix. This approach is frequently referred to as the “sell-through” revenue recognition model. Once the prescription has been provided to the patient, it is not subject to return unless the product is damaged.
	Product sales to our European distribution partner are generally not subject to customer incentives, rights of return or discounts and allowances. We record revenue at the time our European distribution partner has accepted the product, a method also known as the “sell-in” revenue recognition model.
	Product Sales Discounts and Allowances
	We calculate gross product revenues based on the price that we charge our United States specialty pharmacy and our European distribution partner. We estimate our net product revenues by deducting from our gross product revenues (a) trade allowances, such as discounts for prompt payment, (b) estimated government rebates and chargebacks, and (c) estimated costs of patient assistance programs. We initially record estimates for these deductions at the time we recognize the gross revenue. We update our estimates on a recurring basis as new information becomes available. These discounts and allowances apply only to gross product revenues earned in the United States. See “Note 1 - Organization and Summary of Significant Accounting Policies” to our Consolidated Financial Statements included in our Annual Report on Form 10-K for the year ended December 31, 2013 for a further description of those discounts and allowances.
	Cost of Goods Sold
	Cost of goods sold is related to our product revenues and consisted primarily of a 3% royalty and indirect labor costs, and to a lesser extent, the cost of manufacturing and other third party logistics costs of our product. A significant portion of the manufacturing costs for product sales were incurred prior to regulatory approval of COMETRIQ for the treatment of progressive, metastatic MTC and, therefore, were expensed as research and development costs when those costs were incurred, rather than capitalized as inventory.
	In accordance with our product development and commercialization agreement with GlaxoSmithKline, we are required to pay GlaxoSmithKline a 3% royalty on the Net Sales of any product incorporating cabozantinib, including COMETRIQ. Net Sales is defined in the product development and commercialization agreement generally as the gross invoiced sales price less customer credits, rebates, chargebacks, shipping costs, customs duties, and sales tax and other similar tax payments we are required to make.

Restructurings

Restructurings	3 Months Ended
	Mar. 31, 2014
Restructuring Charges [Abstract]	'
Restructurings	'
	RESTRUCTURINGS
	Between March 2010 and May 2013, we implemented five restructurings (referred to collectively as the “Restructurings”) as a consequence of our decision to focus our proprietary resources and development efforts on the development and commercialization of cabozantinib and strategy to manage costs. The aggregate reduction in headcount from the Restructurings was 429 employees. Charges and credits related to the Restructurings were recorded in periods other than those in which the Restructurings were implemented as a result of sublease activities for certain of our buildings in South San Francisco, California, changes in assumptions regarding anticipated sublease activities, the effect of the passage of time on our discounted cash flow computations, previously planned employee terminations, and sales of excess equipment and other assets.
	We have recorded aggregate restructuring charges of $53.3 million in connection with the Restructurings, of which $29.4 million related to facility charges, $21.7 million related to termination benefits, $2.2 million related to the impairment of excess equipment and other assets, and an additional minor amount related to legal and other fees.
	For the three months ended March 31, 2014 and 2013, we recorded restructuring charges of $46 thousand and $0.1 million, respectively. The charges for both periods presented were related to the effect of the passage of time on our discounted cash flow computations. During the three months ended March 31, 2014, those charges were partially offset by $0.1 million in recoveries recorded in connection with the sale of excess equipment and other assets.
	The total outstanding restructuring liability related to the Restructurings is included in the current and long-term portion of restructuring on the accompanying Consolidated Balance Sheets. The components and changes of these liabilities during the annual periods from inception of the restructuring activities through the year ended December 31, 2013 and during the three months ended March 31, 2014 are summarized in the following table (in thousands):
		Facility			Other			Total
		Charges
	Restructuring liability as of December 31, 2012	$	19,202		$	20		$	19,222
	Restructuring charge	662			569			1,231
	Cash payments	(6,331		)	(434		)	(6,765		)
	Adjustments or non-cash credits including stock compensation expense	(73		)	(238		)	(311		)
	Proceeds from sale of assets	—			95			95
	Restructuring liability as of December 31, 2013	13,460			12			13,472
	Restructuring charge (credit)	159			(113		)	46
	Cash payments	(1,403		)	(6		)	(1,409		)
	Adjustments or non-cash credits	9			(86		)	(77		)
	Proceeds from sale of assets	—			199			199
	Restructuring liability as of March 31, 2014	$	12,225		$	6		$	12,231
	We expect to pay accrued facility charges of $12.2 million, net of cash received from our subtenants, through the end of our lease terms of the buildings, the last of which ends in 2017. With respect to our Restructurings, we expect to incur additional restructuring charges of approximately $2.5 million which relates to the effect of the passage of time on our discounted cash flow computations for the exit, in prior periods, of certain of our South San Francisco buildings. These charges will be recorded through the end of the building lease terms, the last of which ends in 2017.
	The Restructurings have resulted in aggregate cash expenditures of $36.6 million, net of $11.3 million in cash received from subtenants and $2.9 million in cash received in connection with the sale of excess equipment and other assets. Net cash expenditures for the Restructurings were $1.2 million and $2.4 million during the three months ended March 31, 2014 and 2013, respectively.
	The restructuring charges that we expect to incur in connection with the Restructurings are subject to a number of assumptions, and actual results may materially differ. We may also incur other material charges not currently contemplated due to events that may occur as a result of, or associated with, the Restructurings.

Cash_and_Investments

Cash and Investments	3 Months Ended
	Mar. 31, 2014
Investments, Debt and Equity Securities [Abstract]	'
Cash and Investments	'
	CASH AND INVESTMENTS
	The following table summarizes cash and cash equivalents, investments, and restricted cash and investments by balance sheet line item as of March 31, 2014 and December 31, 2013 (in thousands):
		March 31, 2014
		Amortized		Gross		Gross			Fair Value
		Cost		Unrealized		Unrealized
				Gains		Losses
	Cash and cash equivalents	$	157,538	$	1	$	—		$	157,539
	Short-term investments	115,931		119		(17		)	116,033
	Short-term restricted cash and investments	12,142		66		—			12,208
	Long-term investments	111,110		54		(9		)	111,155
	Long-term restricted cash and investments	10,768		46		—			10,814
	Total cash and investments	$	407,489	$	286	$	(26	)	$	407,749
		December 31, 2013
		Amortized		Gross		Gross			Fair Value
		Cost		Unrealized		Unrealized
				Gains		Losses
	Cash and cash equivalents	$	103,978	$	—	$	—		$	103,978
	Short-term investments	138,403		94		(22		)	138,475
	Short-term restricted cash and investments	12,173		40		—			12,213
	Long-term investments	144,226		106		(33		)	144,299
	Long-term restricted cash and investments	16,837		60		—			16,897
	Total cash and investments	$	415,617	$	300	$	(55	)	$	415,862
	Under our loan and security agreement with Silicon Valley Bank, we are required to maintain compensating balances on deposit in one or more investment accounts with Silicon Valley Bank or one of its affiliates. The total collateral balances as of March 31, 2014 and December 31, 2013 were $83.2 million and $83.7 million, respectively, and are reflected on the accompanying Consolidated Balance Sheets in short- and long-term investments. See “Note 8 - Debt” to our Consolidated Financial Statements included in our Annual Report on Form 10-K for the year ended December 31, 2013, for more information regarding the collateral balance requirements under our Silicon Valley Bank loan and security agreement.
	All of our cash equivalents and investments are classified as available-for-sale. The following table summarizes our cash equivalents and investments by security type as of March 31, 2014 and December 31, 2013. The amounts presented exclude cash, but include investments classified as cash equivalents (in thousands):
		March 31, 2014
		Amortized		Gross		Gross			Fair Value
		Cost		Unrealized		Unrealized
				Gains		Losses
	Money market funds	$	71,150	$	—	$	—		$	71,150
	Commercial paper	103,273		—		—			103,273
	Corporate bonds	208,208		166		(26		)	208,348
	U.S. Treasury and government sponsored enterprises	21,372		116		—			21,488
	Municipal bonds	2,752		4		—			2,756
	Total investments	$	406,755	$	286	$	(26	)	$	407,015
		December 31, 2013
		Amortized		Gross		Gross			Fair Value
		Cost		Unrealized		Unrealized
				Gains		Losses
	Money market funds	$	24,813	$	—	$	—		$	24,813
	Commercial paper	94,682		—		—			94,682
	Corporate bonds	239,937		190		(55		)	240,072
	U.S. Treasury and government sponsored enterprises	44,284		102		—			44,386
	Municipal bonds	6,005		8					6,013
	Total investments	$	409,721	$	300	$	(55	)	$	409,966
	There were no gains or losses on the sales of investments during the three months ended March 31, 2014 and 2013.
	All of our investments are subject to a quarterly impairment review. During the three months ended March 31, 2014 and 2013, we did not record any other-than-temporary impairment charges on our available-for-sale securities. As of March 31, 2014, there were 27 investments in an unrealized loss position with an aggregate fair value $39.5 million. All of our investments in an unrealized loss position are corporate bonds. All of our investments in an unrealized loss position have been so for less than one year and the unrealized losses were not attributed to credit risk, but rather associated with the changes in interest rates. Based on the scheduled maturities of our investments, we concluded that the unrealized losses in our investment securities are not other-than-temporary, as it is more likely than not that we will hold these investments for a period of time sufficient for a recovery of our cost basis.
	The following summarizes the fair value of securities classified as available-for-sale by contractual maturity as of March 31, 2014 (in thousands):
		Mature within One Year		After One Year through Two Years		Fair Value
	Money market funds	$	71,150	$	—	$	71,150
	Commercial paper	103,273		—		103,273
	Corporate bonds	168,772		39,576		208,348
	U.S. Treasury and government sponsored enterprises	15,400		6,088		21,488
	Municipal bonds	—		2,756		2,756
	Total investments	$	358,595	$	48,420	$	407,015
	Cash is excluded from the table above. The classification of certain compensating balances and restricted investments are dependent upon the term of the underlying restriction on the asset and not the maturity date of the investment. Therefore, certain long-term investments and long-term restricted cash and investments have contractual maturities within one year.

Inventory

Inventory	3 Months Ended
	Mar. 31, 2014
Inventory Disclosure [Abstract]	'
Inventory	'
	INVENTORY
	Inventory consists of the following (in thousands):
		March 31,		December 31,
		2014		2013
	Raw materials	$	678	$	529
	Work in process	1,665		2,280
	Finished goods	343		81
	Total	$	2,686	$	2,890
	We received regulatory approval for our first product, COMETRIQ, on November 29, 2012. A significant portion of the manufacturing costs for our inventory were incurred prior to regulatory approval of COMETRIQ for the treatment of progressive, metastatic MTC and, therefore, were expensed as research and development costs when those costs were incurred, rather than capitalized as inventory.

Debt

Debt	3 Months Ended
	Mar. 31, 2014
Debt Disclosure [Abstract]	'
Debt	'
	DEBT
	The amortized carrying amount of our debt consists of the following (in thousands):
		March 31,			December 31,
		2014			2013
	Convertible Senior Subordinated Notes due 2019	$	169,415		$	165,296
	Secured Convertible Notes due 2015	91,993			99,851
	Silicon Valley Bank term loan	80,000			80,000
	Silicon Valley Bank line of credit	1,611			2,090
	Total debt	343,019			347,237
	Less: current portion	(1,392		)	(11,762		)
	Long-term debt	$	341,627		$	335,475
	See “Note 8 - Debt” to our Consolidated Financial Statements included in our Annual Report on Form 10-K for the year ended December 31, 2013, for additional information on the terms of our debt, including a description of the conversion features of the of 4.25% Convertible Senior Subordinated Notes due 2019 (the “2019 Notes”) and our Secured Convertible Notes due June 2015 (the “Deerfield Notes”).
	Convertible Senior Subordinated Notes due 2019
	In August 2012, we issued and sold $287.5 million aggregate principal amount the 2019 Notes. As of March 31, 2014, the entire principal balance remains outstanding. The following is a summary of the liability component of the 2019 Notes (in thousands):
		March 31,			December 31,
		2014			2013
	Net carrying amount of the liability component	$	169,415		$	165,296
	Unamortized discount of the liability component	118,085			122,204
	Face amount of the 2019 Notes	$	287,500		$	287,500
	The debt discount and debt issuance costs will be amortized as interest expense through August 2019. During the three months ended March 31, 2014, total interest expense was $7.4 million, including stated coupon interest of $3.1 million and the amortization of the debt discount and debt issuance costs of $4.3 million. During the three months ended March 31, 2013, total interest expense was $7.0 million including stated coupon interest of $3.1 million and the amortization of the debt discount and debt issuance costs of $3.9 million. The balance of unamortized fees and costs was $3.8 million and $4.0 million as of March 31, 2014 and December 31, 2013, respectively, which is included in Other assets on the accompanying Consolidated Balance Sheets.
	Secured Convertible Notes due June 2015
	In June 2010, we entered into a note purchase agreement with entities affiliated with Deerfield Management Company, L.P. (“Deerfield”), pursuant to which, on July 1, 2010, we sold to Deerfield an aggregate of $124.0 million initial principal amount of the Deerfield Notes. As of March 31, 2014 and December 31, 2013, the remaining outstanding principal balance on the Deerfield Notes was $104.0 million and $114.0 million, respectively, which, subject to certain limitations, is payable in cash or in stock at our discretion. During the three months ended March 31, 2014, and 2013, total interest expense for the Deerfield Notes was $4.2 million and $3.9 million, respectively, including the stated coupon rate and the amortization of the debt discount and debt issuance costs. The non-cash expense relating to the amortization of the debt discount and debt issuance costs was $2.7 million and $2.4 million, during the three months ended March 31, 2014 and 2013, respectively. The balance of unamortized fees and costs was $3.6 million and $1.4 million as of March 31, 2014 and December 31, 2013, respectively, which is included in Other assets on the accompanying Consolidated Balance Sheets.
	On January 22, 2014, the note purchase agreement was amended to provide us with an option to extend the maturity date of our indebtedness under the note purchase agreement to July 1, 2018 (the “Extension Option”). Under the terms of the Extension Option, which expires on March 31, 2015, we have the right to require Deerfield Partners, L.P. and Deerfield International Master Fund, L.P. (the “New Deerfield Purchasers”) to acquire $100 million principal amount of the Deerfield Notes and extend the maturity date to July 1, 2018. If we exercise the Extension Option, the Deerfield Notes would bear interest on and after July 2, 2015 at the rate of 7.5% per annum to be paid in cash, quarterly in arrears, and 7.5% per annum to be paid in kind, quarterly in arrears, for a total interest rate of 15% per annum. We are under no obligation to exercise the Extension Option.
	In connection with the amendment to the note purchase agreement, on January 22, 2014 we issued to the New Deerfield Purchasers two-year warrants (the “2014 Deerfield Warrants”) to purchase an aggregate of 1,000,000 shares of our common stock at an exercise price of $9.70 per share, which exercise price is subject to change in the event we exercise the Extension Option. See “Note 6 - Common Stock and Warrants” for further information on those warrants.
	We determined that the amendment resulted in the Deerfield Notes being modified. In connection with the amendment, we recorded a $2.8 million deferred commitment fee upon the issuance of the 2014 Deerfield Warrants. See “Note 6 - Common Stock and Warrants” for further information on those warrants. The deferred commitment fee is included in Other assets and will be amortized into interest expense as a yield adjustment through the current maturity date of the Deerfield Notes, July 1, 2015. Third-party expenses, comprised primarily of legal and accounting fees, were expensed as of the date of the amendment.

Common_Stock_And_Warrants

Common Stock And Warrants	3 Months Ended
	Mar. 31, 2014
Warrants and Rights Note Disclosure [Abstract]	'
Common Stock And Warrants	'
	COMMON STOCK AND WARRANTS
	Sale of Shares of Common Stock
	In January 2014 we completed a registered underwritten public offering of 10.0 million shares of our common stock at a price of $8.00 per share pursuant to a shelf registration statement previously filed with the SEC, which the SEC declared effective on June 8, 2012. We received $75.6 million in net proceeds from the offering after deducting the underwriting discount and related offering expenses.
	Warrants
	On January 22, 2014, in connection with the amendment to the note purchase agreement to provide us with the Extension Option, we issued to the New Deerfield Purchasers the 2014 Deerfield Warrants to purchase an aggregate of 1,000,000 shares of our common stock at an exercise price of $9.70 per share. If we exercise the Extension Option, the term of the 2014 Deerfield Warrants will be extended by two years and the exercise price will be reset to the lower of (i) the existing exercise price and (ii) 120% of the volume weighted average price of our common stock for the ten trading days immediately following the date of such extension election. Due to the potential increase in term and decrease of the exercise price, the 2014 Deerfield Warrants were recorded as a liability which is included in Other long-term liabilities. The 2014 Deerfield Warrants are recorded at fair value, on a recurring basis, which was $1.0 million and $2.8 million as of March 31, 2014 and January 22, 2014, respectively. We recorded an unrealized gain on the warrants of $1.7 million during the three months ended March 31, 2014 which is included in Interest income and other, net. See “Note 7 - Fair Value Measurements” for more information on the valuation of these warrants.
	At March 31, 2014, the following warrants to purchase common stock were outstanding and exercisable:
	Date Issued	Exercise		Expiration Date	Number
		Price per Share			of Shares
	June 4, 2008	$	7.4	June 4, 2014	1,000,000
	June 10, 2009	$	6.05	June 10, 2014	186,362
	January 22, 2014	$	9.7	January 22, 2016	1,000,000
					2,186,362
	The warrants issued in June 2008 and January 2014 are Participating Securities. The warrant holders do not have a contractual obligation to share in our losses.

Fair_Value_Measurements

Fair Value Measurements	3 Months Ended
	Mar. 31, 2014
Fair Value Disclosures [Abstract]	'
Fair Value Measurements	'
	FAIR VALUE MEASUREMENTS
	The following table sets forth the fair value of our financial assets and liabilities that were measured and recorded on a recurring basis as of March 31, 2014 and December 31, 2013. We did not have any financial liabilities that were measured and recorded on a recurring basis or Level 3 investments as of December 31, 2013. The amounts presented exclude cash, but include investments classified as cash equivalents (in thousands):
		March 31, 2014
		Level 1			Level 2			Level 3		Total
	Financial assets:
	Money market funds	$	71,150		$	—		$	—	$	71,150
	Commercial paper	—			103,273			—		103,273
	Corporate bonds	—			208,348			—		208,348
	U.S. Treasury and government sponsored enterprises	—			21,488			—		21,488
	Municipal bonds	—			2,756			—		2,756
	Total financial assets	$	71,150		$	335,865		$	—	$	407,015
	Financial liabilities:
	Warrants	$	—		$	—		$	1,022	$	1,022
	Total financial liabilities	$	—		$	—		$	1,022	$	1,022
		December 31, 2013
		Level 1			Level 2			Total
	Money market funds	$	24,813		$	—		$	24,813
	Commercial paper	—			94,682			94,682
	Corporate bonds	—			240,072			240,072
	U.S. Treasury and government sponsored enterprises	—			44,386			44,386
	Municipal bonds	—			6,013			6,013
	Total financial assets	$	24,813		$	385,153		$	409,966
	There were no transfers between any of the fair value hierarchies, as determined at the end of each reporting period.
	The estimated fair values of our financial instruments that are carried at amortized cost for which it is practicable to determine a fair value were as follows (in thousands):
		March 31, 2014						December 31, 2013
		Carrying			Fair Value			Carrying		Fair Value
		Amount						Amount
	2019 Notes	$	169,415		$	255,731		$	165,296	$	339,883
	Silicon Valley Bank term loan	$	80,000		$	79,900		$	80,000	$	79,946
	Silicon Valley Bank line of credit	$	1,611		$	1,611		$	2,090	$	2,090
	We believe it is not practicable to determine the fair value of the Deerfield Notes due to the unique structure of the instrument that was financed by entities affiliated with Deerfield.
	The carrying amounts of cash, trade and other receivables, accounts payable and accrued clinical trial liabilities approximate their fair values and are excluded from the tables above.
	The following methods and assumptions were used to estimate the fair value of each class of financial instrument for which it is practicable to estimate a value:
	•	When available, we value investments based on quoted prices for those financial instruments, which is a Level 1 input. Our remaining investments are valued using third-party pricing sources, which use observable market prices, interest rates and yield curves observable at commonly quoted intervals of similar assets as observable inputs for pricing, which is a Level 2 input.
	•	The 2019 Notes are valued using a third-party pricing model that is based in part on average trading prices, which is a Level 2 input. The 2019 Notes are not marked-to-market and are shown at their initial fair value less the unamortized discount; the portion of the value allocated to the conversion option is included in Stockholders’ equity on the accompanying Consolidated Balance Sheets.
	•	We estimate the fair value of our other debt instruments, where possible, using the net present value of the payments discounted at an interest rate that is consistent with money-market rates that would have been earned on our non-interest-bearing compensating balances, which is a Level 2 input.
	•	The 2014 Deerfield Warrants are valued using a Monte Carlo simulation model. The expected life is based on the contractual terms of the 2014 Deerfield Warrants, and in certain simulations, assumes the two year extension that would result from our exercise of the Extension Option. We consider implied volatility as well as our historical volatility in developing our estimate of expected volatility. The fair value of the 2014 Deerfield Warrants were estimated using the following assumptions, which, except for risk-free interest rate, are Level 3 inputs (dollars in thousands):
					22-Jan-14
		31-Mar-14			(issuance date)
	Fair value of warrants	$	1,022		$	2,762
	Risk-free interest rate	0.98		%	0.95		%
	Dividend yield	—		%	—		%
	Volatility	84		%	57		%
	Average expected life	3.0 years			3.2 years

StockBased_Compensation

Stock-Based Compensation	3 Months Ended
	Mar. 31, 2014
Share-based Compensation [Abstract]	'
Stock-Based Compensation	'
	STOCK-BASED COMPENSATION
	We recorded and allocated employee stock-based compensation expenses for our equity incentive plans and our 2000 Employee Stock Purchase Plan (“ESPP”) as follows (in thousands):
		Three Months Ended March 31,
		2014				2013
	Research and development expense	$	1,565			$	1,407
	Selling, general and administrative expense	2,193				1,268
	Total employee stock-based compensation expense	$	3,758			$	2,675
	We use the Black-Scholes option pricing model to value our stock options. The expected life computation is based on historical exercise patterns and post-vesting termination behavior. We considered implied volatility as well as our historical volatility in developing our estimate of expected volatility. The fair value of employee stock option awards and ESPP purchases was estimated using the following assumptions and weighted average fair values:
		Stock Options
		Three Months Ended March 31,
		2014				2013
	Weighted average grant-date fair value	$	4.7			$	2.45
	Risk-free interest rate	1.59		%		0.78		%
	Dividend yield	—		%		—		%
	Volatility	81		%		62		%
	Expected life	5.5 years				5.2 years
		Employee Stock Purchase Plan
		Three Months Ended March 31,
		2014				2013
	Weighted average grant-date fair value	$	1.59			$	1.59
	Risk-free interest rate	0.08		%		0.15		%
	Dividend yield	—		%		—		%
	Volatility	62		%		67		%
	Expected life	6 months				6 months
	Of the stock options outstanding as of March 31, 2014, 3,720,752 were granted subject to performance objectives tied to the achievement of goals set by the Compensation Committee of our Board of Directors and will vest in full or part based on achievement of such goals. As of March 31, 2014, we expect that achievement of some of those performance objectives is probable and have, therefore, recorded for stock-based compensation expense in connection with such awards. We have not included any stock-based compensation expense for stock options with performance objectives where the performance goals cannot be reasonably assured of achievement; the grant date fair value of such awards was $6.9 million.
	A summary of all stock option activity for the three months ended March 31, 2014 is presented below (dollars in thousands, except per share amounts):
		Shares			Weighted				Weighted	Aggregate
					Average				Average	Intrinsic
					Exercise Price				Remaining Contractual	Value
									Term (Years)
	Options outstanding at December 31, 2013	23,983,275			$	6.48
	Granted	626,290			$	6.96
	Exercised	(19,090	)		$	6.28
	Forfeited	(5,979	)		$	5.73
	Expired	(352,342	)		$	7.75
	Options outstanding at March 31, 2014	24,232,154			$	6.47			4.46	$	2
	Exercisable at March 31, 2014	14,057,195			$	7.12			3.35	$	2
	As of March 31, 2014, $26.6 million of total unrecognized compensation expense related to employee stock options was expected to be recognized over a weighted-average period of 2.52 years.
	A summary of all restricted stock unit (“RSU”) activity for the three months ended March 31, 2014 is presented below (dollars in thousands, except per share amounts):
		Shares			Weighted				Weighted	Aggregate
					Average				Average	Intrinsic
					Grant Date				Remaining	Value
					Fair Value				Contractual
									Term (Years)
	Awards outstanding at December 31, 2013	1,810,521			$	5.56
	Awarded	32,096			$	6.77
	Released	(81,590	)		$	7.11
	Forfeited	(14,687	)		$	5.56
	Awards outstanding at March 31, 2014	1,746,340			$	5.51			3.18	$	5,903
	As of March 31, 2014, $6.7 million of total unrecognized compensation expense related to employee RSUs was expected to be recognized over a weighted-average period of 3.18 years.

Net_Loss_Per_Share

Net Loss Per Share	3 Months Ended
	Mar. 31, 2014
Earnings Per Share [Abstract]	'
Net Loss Per Share	'
	NET LOSS PER SHARE
	The following table sets forth a reconciliation of basic and diluted net loss per share (in thousands, except per share amounts):
		Three Months Ended March 31,
		2014				2013
	Numerator:
	Net loss	$	(74,619	)		$	(44,729	)
	Denominator:
	Shares used in computing basic and diluted net loss per share	191,699				183,742
	Net loss per share, basic and diluted	$	(0.39	)		$	(0.24	)
	The following table sets forth outstanding potential shares of common stock that are not included in the computation of diluted net loss per share because, to do so would be anti-dilutive (in thousands):
		31-Mar
		2014			2013
	Convertible debt	54,123			54,123
	Outstanding stock options, unvested RSUs and ESPP contributions	26,302			18,181
	Warrants	2,186			1,441
	Total potentially dilutive shares	82,611			73,745

Concentrations_of_Credit_Risk

Concentrations of Credit Risk	3 Months Ended
	Mar. 31, 2014
Risks and Uncertainties [Abstract]	'
Concentrations of Credit Risk	'
	CONCENTRATIONS OF CREDIT RISK
	Financial instruments that potentially subject us to concentrations of credit risk are primarily trade and other receivables and investments. Investments consist of money market funds, taxable commercial paper, corporate bonds with high credit quality, U.S. Treasury and government sponsored enterprises, and municipal bonds. All investments are maintained with financial institutions that management believes are creditworthy.
	Trade and other receivables are unsecured and are concentrated in the pharmaceutical and biotechnology industries. Accordingly, we may be exposed to credit risk generally associated with pharmaceutical and biotechnology companies. We have incurred no bad debt expense since inception. As of March 31, 2014, 70% of our trade receivables are with the specialty pharmacy that sells COMETRIQ in the United States and 6% are with our European distribution partner. Both of these customers pay promptly and within their respective payment terms.
	We have operations primarily in the United States, while some of our collaboration partners have headquarters outside of the United States and certain of our clinical trials for cabozantinib are conducted outside of the United States. During the three months ended March 31, 2013, 100% of our revenues were earned in the United States. During the second quarter of 2013, we initiated a Named Patient Use (“NPU”) program through our distribution partner, Swedish Orphan Biovitrum, to support the distribution and commercialization of COMETRIQ for metastatic MTC primarily in the European Union and potentially other countries. During the three months ended March 31, 2014, 98%, of our revenues were earned in the United States; the remainder of our revenues were earned in the European Union under this NPU program. All of our long-lived assets are located in the United States.
	The following table sets forth the percentage of revenues recognized under our collaboration agreements and product sales to the specialty pharmacy that represent 10% or more of total revenues during the three months ended March 31, 2014 and 2013:
		Three Months Ended March 31,
		2014		2013
	Collaboration agreement:
	Bristol-Myers Squibb	—	%	81	%
	Product sales:
	Diplomat Specialty Pharmacy	98	%	19	%

Organization_and_Summary_of_Si1

Organization and Summary of Significant Accounting Policies (Policies)	3 Months Ended
	Mar. 31, 2014
Organization, Consolidation and Presentation of Financial Statements [Abstract]	'
Organization	'
	Organization
	Exelixis, Inc. (“Exelixis,” “we,” “our” or “us”) is a biopharmaceutical company committed to developing small molecule therapies for the treatment of cancer. Our two most advanced assets, COMETRIQ® (cabozantinib), our wholly-owned inhibitor of multiple receptor tyrosine kinases, and cobimetinib (GDC-0973/XL518), a potent, highly selective inhibitor of MEK, which we out-licensed to Genentech, Inc. (a member of the Roche Group) (“Genentech”), are currently the subject of six ongoing phase 3 pivotal trials.
	We are focusing our development and commercialization efforts primarily on COMETRIQ (cabozantinib), which was approved by the U.S. Food and Drug Administration (“FDA”) on November 29, 2012, for the treatment of progressive, metastatic medullary thyroid cancer (“MTC”) in the United States, where it became commercially available in late January 2013. In March 2014, the European Commission approved COMETRIQ for the treatment of adult patients with progressive, unresectable locally advanced or metastatic MTC. The European Commission granted conditional marketing authorization following a positive opinion from the European Committee for Medicinal Products for Human Use (“CHMP”) issued in December 2013.
Basis of Consolidation	'
	Basis of Consolidation
	The consolidated financial statements include the accounts of Exelixis and those of our wholly-owned subsidiaries. These entities’ functional currency is the U.S. dollar. All intercompany balances and transactions have been eliminated.
Basis of Presentation	'
	Basis of Presentation
	The accompanying unaudited consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States for interim financial information and pursuant to Form 10-Q and Article 10 of Regulation S-X of the Securities and Exchange Commission (“SEC”). Accordingly, they do not include all of the information and footnotes required by U.S. generally accepted accounting principles for complete financial statements. In our opinion, all adjustments (consisting only of normal recurring adjustments) considered necessary for a fair presentation of the results of operations and cash flows for the period presented have been included.
	Exelixis adopted a 52- or 53-week fiscal year that generally ends on the Friday closest to December 31st. Fiscal year 2013, a 52-week year, ended on December 27, 2013, and fiscal year 2014, a 53-week year, will end on January 2, 2015. For convenience, references in this report as of and for the fiscal quarters ended March 29, 2013 and March 28, 2014, and as of the fiscal year ended December 27, 2013, are indicated as ended March 31, 2013, March 31, 2014, and December 31, 2013, respectively.
	Operating results for the three months ended March 31, 2014 are not necessarily indicative of the results that may be expected for the fiscal year ending January 2, 2015 or for any future period. These financial statements and notes should be read in conjunction with the consolidated financial statements and notes thereto for the year ended December 31, 2013, included in our Annual Report on Form 10-K filed with the SEC on February 20, 2014.
Fiscal Period, Policy	'
	Exelixis adopted a 52- or 53-week fiscal year that generally ends on the Friday closest to December 31st. Fiscal year 2013, a 52-week year, ended on December 27, 2013, and fiscal year 2014, a 53-week year, will end on January 2, 2015. For convenience, references in this report as of and for the fiscal quarters ended March 29, 2013 and March 28, 2014, and as of the fiscal year ended December 27, 2013, are indicated as ended March 31, 2013, March 31, 2014, and December 31, 2013, respectively.
Segment Information	'
	Segment Information
	We operate as a single reportable segment.
Use of Estimates	'
	Use of Estimates
	The preparation of our consolidated financial statements is in conformity with accounting principles generally accepted in the United States which requires management to make judgments, estimates and assumptions that affect the reported amounts of assets, liabilities, revenue and expenses, and related disclosures. On an ongoing basis, management evaluates its estimates including, but not limited to, those related to inventory, revenue recognition, valuation of long-lived assets, certain accrued liabilities including clinical trial accruals and restructuring liability, valuation of warrants, share-based compensation and the valuation of the debt and equity components of our convertible debt at issuance. We base our estimates on historical experience and on various other market-specific and other relevant assumptions that we believe to be reasonable under the circumstances, the results of which form the basis for making judgments about the carrying values of assets and liabilities that are not readily apparent from other sources. Actual results could differ materially from those estimates.
Revenue Recognition	'
	Revenue Recognition
	We recognize revenue from the sale of COMETRIQ and from license fees and milestones earned on research and collaboration arrangements. See “Note 1 - Organization and Summary of Significant Accounting Policies” to our Consolidated Financial Statements included in our Annual Report on Form 10-K for the year ended December 31, 2013 for a description of our policies for revenue recognition on research and collaboration agreements. We did not enter into any new collaboration agreements during the three months ended March 31, 2014. See “Note 2 - Research and Collaboration Agreements” to our Consolidated Financial Statements included in our Annual Report on Form 10-K for the year ended December 31, 2013 for a description of our existing collaboration agreements.
	Net Product Revenues
	We recognize revenue when it is both realized or realizable and earned, meaning persuasive evidence of an arrangement exists, delivery has occurred, title has transferred, the price is fixed or determinable, there are no remaining customer acceptance requirements, and collectability of the resulting receivable is reasonably assured. For product sales in the United States, this generally occurs upon shipment of the product to the patient by our distributor. For product sales in Europe, this occurs when our European distribution partner has accepted the product.
	We sell our product, COMETRIQ, in the United States to a specialty pharmacy that benefits from customer incentives and has a right of return. We have a limited sales history and cannot reliably estimate expected returns of the product nor the discounts and rebates due to payors at the time of shipment to the specialty pharmacy. Accordingly, upon shipment to the specialty pharmacy, we record deferred revenue on our Consolidated Balance Sheets. We recognize revenue when the specialty pharmacy provides the product to a patient based on the fulfillment of a prescription. We record revenue using an analysis of prescription data from our specialty pharmacy to ascertain the date of shipment and the payor mix. This approach is frequently referred to as the “sell-through” revenue recognition model. Once the prescription has been provided to the patient, it is not subject to return unless the product is damaged.
	Product sales to our European distribution partner are generally not subject to customer incentives, rights of return or discounts and allowances. We record revenue at the time our European distribution partner has accepted the product, a method also known as the “sell-in” revenue recognition model.
	Product Sales Discounts and Allowances
	We calculate gross product revenues based on the price that we charge our United States specialty pharmacy and our European distribution partner. We estimate our net product revenues by deducting from our gross product revenues (a) trade allowances, such as discounts for prompt payment, (b) estimated government rebates and chargebacks, and (c) estimated costs of patient assistance programs. We initially record estimates for these deductions at the time we recognize the gross revenue. We update our estimates on a recurring basis as new information becomes available. These discounts and allowances apply only to gross product revenues earned in the United States. See “Note 1 - Organization and Summary of Significant Accounting Policies” to our Consolidated Financial Statements included in our Annual Report on Form 10-K for the year ended December 31, 2013 for a further description of those discounts and allowances.
Cost of Goods Sold	'
	Cost of Goods Sold
	Cost of goods sold is related to our product revenues and consisted primarily of a 3% royalty and indirect labor costs, and to a lesser extent, the cost of manufacturing and other third party logistics costs of our product. A significant portion of the manufacturing costs for product sales were incurred prior to regulatory approval of COMETRIQ for the treatment of progressive, metastatic MTC and, therefore, were expensed as research and development costs when those costs were incurred, rather than capitalized as inventory.
	In accordance with our product development and commercialization agreement with GlaxoSmithKline, we are required to pay GlaxoSmithKline a 3% royalty on the Net Sales of any product incorporating cabozantinib, including COMETRIQ. Net Sales is defined in the product development and commercialization agreement generally as the gross invoiced sales price less customer credits, rebates, chargebacks, shipping costs, customs duties, and sales tax and other similar tax payments we are required to make.

Restructurings_Tables

Restructurings (Tables)	3 Months Ended
	Mar. 31, 2014
Restructuring Charges [Abstract]	'
Summary Of Components Of Restructuring Liability	'
	The components and changes of these liabilities during the annual periods from inception of the restructuring activities through the year ended December 31, 2013 and during the three months ended March 31, 2014 are summarized in the following table (in thousands):
		Facility			Other			Total
		Charges
	Restructuring liability as of December 31, 2012	$	19,202		$	20		$	19,222
	Restructuring charge	662			569			1,231
	Cash payments	(6,331		)	(434		)	(6,765		)
	Adjustments or non-cash credits including stock compensation expense	(73		)	(238		)	(311		)
	Proceeds from sale of assets	—			95			95
	Restructuring liability as of December 31, 2013	13,460			12			13,472
	Restructuring charge (credit)	159			(113		)	46
	Cash payments	(1,403		)	(6		)	(1,409		)
	Adjustments or non-cash credits	9			(86		)	(77		)
	Proceeds from sale of assets	—			199			199
	Restructuring liability as of March 31, 2014	$	12,225		$	6		$	12,231

Cash_and_Investments_Cash_and_

Cash and Investments Cash and Investments (Tables)	3 Months Ended
	Mar. 31, 2014
Investments, Debt and Equity Securities [Abstract]	'
Schedule of Available-for-Sale Securities	'
	The following table summarizes cash and cash equivalents, investments, and restricted cash and investments by balance sheet line item as of March 31, 2014 and December 31, 2013 (in thousands):
		March 31, 2014
		Amortized		Gross		Gross			Fair Value
		Cost		Unrealized		Unrealized
				Gains		Losses
	Cash and cash equivalents	$	157,538	$	1	$	—		$	157,539
	Short-term investments	115,931		119		(17		)	116,033
	Short-term restricted cash and investments	12,142		66		—			12,208
	Long-term investments	111,110		54		(9		)	111,155
	Long-term restricted cash and investments	10,768		46		—			10,814
	Total cash and investments	$	407,489	$	286	$	(26	)	$	407,749
		December 31, 2013
		Amortized		Gross		Gross			Fair Value
		Cost		Unrealized		Unrealized
				Gains		Losses
	Cash and cash equivalents	$	103,978	$	—	$	—		$	103,978
	Short-term investments	138,403		94		(22		)	138,475
	Short-term restricted cash and investments	12,173		40		—			12,213
	Long-term investments	144,226		106		(33		)	144,299
	Long-term restricted cash and investments	16,837		60		—			16,897
	Total cash and investments	$	415,617	$	300	$	(55	)	$	415,862
Summary of Cash and Investments by Security Type	'
	The amounts presented exclude cash, but include investments classified as cash equivalents (in thousands):
		March 31, 2014
		Amortized		Gross		Gross			Fair Value
		Cost		Unrealized		Unrealized
				Gains		Losses
	Money market funds	$	71,150	$	—	$	—		$	71,150
	Commercial paper	103,273		—		—			103,273
	Corporate bonds	208,208		166		(26		)	208,348
	U.S. Treasury and government sponsored enterprises	21,372		116		—			21,488
	Municipal bonds	2,752		4		—			2,756
	Total investments	$	406,755	$	286	$	(26	)	$	407,015
		December 31, 2013
		Amortized		Gross		Gross			Fair Value
		Cost		Unrealized		Unrealized
				Gains		Losses
	Money market funds	$	24,813	$	—	$	—		$	24,813
	Commercial paper	94,682		—		—			94,682
	Corporate bonds	239,937		190		(55		)	240,072
	U.S. Treasury and government sponsored enterprises	44,284		102		—			44,386
	Municipal bonds	6,005		8					6,013
	Total investments	$	409,721	$	300	$	(55	)	$	409,966
Summary of Available-for-Sale Securities by Contractual Maturity	'
	The following summarizes the fair value of securities classified as available-for-sale by contractual maturity as of March 31, 2014 (in thousands):
		Mature within One Year		After One Year through Two Years		Fair Value
	Money market funds	$	71,150	$	—	$	71,150
	Commercial paper	103,273		—		103,273
	Corporate bonds	168,772		39,576		208,348
	U.S. Treasury and government sponsored enterprises	15,400		6,088		21,488
	Municipal bonds	—		2,756		2,756
	Total investments	$	358,595	$	48,420	$	407,015

Inventory_Tables

Inventory (Tables)	3 Months Ended
	Mar. 31, 2014
Inventory Disclosure [Abstract]	'
Schedule of Inventory	'
	Inventory consists of the following (in thousands):
		March 31,		December 31,
		2014		2013
	Raw materials	$	678	$	529
	Work in process	1,665		2,280
	Finished goods	343		81
	Total	$	2,686	$	2,890

Debt_Tables

Debt (Tables)	3 Months Ended
	Mar. 31, 2014
Debt Disclosure [Abstract]	'
Schedule Of Debt	'
	The amortized carrying amount of our debt consists of the following (in thousands):
		March 31,			December 31,
		2014			2013
	Convertible Senior Subordinated Notes due 2019	$	169,415		$	165,296
	Secured Convertible Notes due 2015	91,993			99,851
	Silicon Valley Bank term loan	80,000			80,000
	Silicon Valley Bank line of credit	1,611			2,090
	Total debt	343,019			347,237
	Less: current portion	(1,392		)	(11,762		)
	Long-term debt	$	341,627		$	335,475
Summary Of The Liability Component Of The 2019 Notes	'
	The following is a summary of the liability component of the 2019 Notes (in thousands):
		March 31,			December 31,
		2014			2013
	Net carrying amount of the liability component	$	169,415		$	165,296
	Unamortized discount of the liability component	118,085			122,204
	Face amount of the 2019 Notes	$	287,500		$	287,500

Common_Stock_And_Warrants_Tabl

Common Stock And Warrants (Tables)	3 Months Ended
	Mar. 31, 2014
Warrants and Rights Note Disclosure [Abstract]	'
Schedule Of Warrants To Purchase Common Stock Outstanding And Exercisable	'
	At March 31, 2014, the following warrants to purchase common stock were outstanding and exercisable:
	Date Issued	Exercise		Expiration Date	Number
		Price per Share			of Shares
	June 4, 2008	$	7.4	June 4, 2014	1,000,000
	June 10, 2009	$	6.05	June 10, 2014	186,362
	January 22, 2014	$	9.7	January 22, 2016	1,000,000
					2,186,362

Fair_Value_Measurements_Fair_V

Fair Value Measurements Fair Value Measurements (Tables)	3 Months Ended
	Mar. 31, 2014
Fair Value Disclosures [Abstract]	'
Schedule Of Fair Value Of Financial Assets Measured On A Recurring Basis	'
	The amounts presented exclude cash, but include investments classified as cash equivalents (in thousands):
		March 31, 2014
		Level 1			Level 2			Level 3		Total
	Financial assets:
	Money market funds	$	71,150		$	—		$	—	$	71,150
	Commercial paper	—			103,273			—		103,273
	Corporate bonds	—			208,348			—		208,348
	U.S. Treasury and government sponsored enterprises	—			21,488			—		21,488
	Municipal bonds	—			2,756			—		2,756
	Total financial assets	$	71,150		$	335,865		$	—	$	407,015
	Financial liabilities:
	Warrants	$	—		$	—		$	1,022	$	1,022
	Total financial liabilities	$	—		$	—		$	1,022	$	1,022
		December 31, 2013
		Level 1			Level 2			Total
	Money market funds	$	24,813		$	—		$	24,813
	Commercial paper	—			94,682			94,682
	Corporate bonds	—			240,072			240,072
	U.S. Treasury and government sponsored enterprises	—			44,386			44,386
	Municipal bonds	—			6,013			6,013
	Total financial assets	$	24,813		$	385,153		$	409,966
Schedule Of Estimated Fair Value Of Outstanding Debt	'
	The estimated fair values of our financial instruments that are carried at amortized cost for which it is practicable to determine a fair value were as follows (in thousands):
		March 31, 2014						December 31, 2013
		Carrying			Fair Value			Carrying		Fair Value
		Amount						Amount
	2019 Notes	$	169,415		$	255,731		$	165,296	$	339,883
	Silicon Valley Bank term loan	$	80,000		$	79,900		$	80,000	$	79,946
	Silicon Valley Bank line of credit	$	1,611		$	1,611		$	2,090	$	2,090
Schedule of Assumptions Used	'
	The fair value of the 2014 Deerfield Warrants were estimated using the following assumptions, which, except for risk-free interest rate, are Level 3 inputs (dollars in thousands):
					22-Jan-14
		31-Mar-14			(issuance date)
	Fair value of warrants	$	1,022		$	2,762
	Risk-free interest rate	0.98		%	0.95		%
	Dividend yield	—		%	—		%
	Volatility	84		%	57		%
	Average expected life	3.0 years			3.2 years

StockBased_Compensation_Tables

Stock-Based Compensation (Tables)	3 Months Ended
	Mar. 31, 2014
Share-based Compensation [Abstract]	'
Schedule Of Allocated Employee Stock-Based Compensation Expenses	'
	We recorded and allocated employee stock-based compensation expenses for our equity incentive plans and our 2000 Employee Stock Purchase Plan (“ESPP”) as follows (in thousands):
		Three Months Ended March 31,
		2014				2013
	Research and development expense	$	1,565			$	1,407
	Selling, general and administrative expense	2,193				1,268
	Total employee stock-based compensation expense	$	3,758			$	2,675
Schedule Of Fair Value Of Employee Share-Based Payments Awards Estimated Using The Assumptions And Weighted Average Fair Values	'
	The fair value of employee stock option awards and ESPP purchases was estimated using the following assumptions and weighted average fair values:
		Stock Options
		Three Months Ended March 31,
		2014				2013
	Weighted average grant-date fair value	$	4.7			$	2.45
	Risk-free interest rate	1.59		%		0.78		%
	Dividend yield	—		%		—		%
	Volatility	81		%		62		%
	Expected life	5.5 years				5.2 years
		Employee Stock Purchase Plan
		Three Months Ended March 31,
		2014				2013
	Weighted average grant-date fair value	$	1.59			$	1.59
	Risk-free interest rate	0.08		%		0.15		%
	Dividend yield	—		%		—		%
	Volatility	62		%		67		%
	Expected life	6 months				6 months
Summary Of All Stock Option Activity	'
	A summary of all stock option activity for the three months ended March 31, 2014 is presented below (dollars in thousands, except per share amounts):
		Shares			Weighted				Weighted	Aggregate
					Average				Average	Intrinsic
					Exercise Price				Remaining Contractual	Value
									Term (Years)
	Options outstanding at December 31, 2013	23,983,275			$	6.48
	Granted	626,290			$	6.96
	Exercised	(19,090	)		$	6.28
	Forfeited	(5,979	)		$	5.73
	Expired	(352,342	)		$	7.75
	Options outstanding at March 31, 2014	24,232,154			$	6.47			4.46	$	2
	Exercisable at March 31, 2014	14,057,195			$	7.12			3.35	$	2
Summary Of All RSU Activity	'
	A summary of all restricted stock unit (“RSU”) activity for the three months ended March 31, 2014 is presented below (dollars in thousands, except per share amounts):
		Shares			Weighted				Weighted	Aggregate
					Average				Average	Intrinsic
					Grant Date				Remaining	Value
					Fair Value				Contractual
									Term (Years)
	Awards outstanding at December 31, 2013	1,810,521			$	5.56
	Awarded	32,096			$	6.77
	Released	(81,590	)		$	7.11
	Forfeited	(14,687	)		$	5.56
	Awards outstanding at March 31, 2014	1,746,340			$	5.51			3.18	$	5,903

Net_Loss_Per_Share_Tables

Net Loss Per Share (Tables)	3 Months Ended
	Mar. 31, 2014
Earnings Per Share [Abstract]	'
Schedule Of Reconciliation Of Basic And Diluted Net Income (Loss) Per Share	'
	The following table sets forth a reconciliation of basic and diluted net loss per share (in thousands, except per share amounts):
		Three Months Ended March 31,
		2014				2013
	Numerator:
	Net loss	$	(74,619	)		$	(44,729	)
	Denominator:
	Shares used in computing basic and diluted net loss per share	191,699				183,742
	Net loss per share, basic and diluted	$	(0.39	)		$	(0.24	)
Schedule Of Potential Shares Of Common Stock Not Included In Computation Of Diluted Net Loss Per Share	'
	The following table sets forth outstanding potential shares of common stock that are not included in the computation of diluted net loss per share because, to do so would be anti-dilutive (in thousands):
		31-Mar
		2014			2013
	Convertible debt	54,123			54,123
	Outstanding stock options, unvested RSUs and ESPP contributions	26,302			18,181
	Warrants	2,186			1,441
	Total potentially dilutive shares	82,611			73,745

Concentrations_of_Credit_Risk_

Concentrations of Credit Risk (Tables)	3 Months Ended
	Mar. 31, 2014
Risks and Uncertainties [Abstract]	'
Schedules of collaborators that represent 10% or more of total revenues	'
	The following table sets forth the percentage of revenues recognized under our collaboration agreements and product sales to the specialty pharmacy that represent 10% or more of total revenues during the three months ended March 31, 2014 and 2013:
		Three Months Ended March 31,
		2014		2013
	Collaboration agreement:
	Bristol-Myers Squibb	—	%	81	%
	Product sales:
	Diplomat Specialty Pharmacy	98	%	19	%

Organization_and_Summary_of_Si2

Organization and Summary of Significant Accounting Policies (Details)	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
	segment
	trial
Operations [Line Items]	'	'
Operating Cycle	'371 days	'364 days
Number of trials in process	6	'
Number of operating segments	1	'
Glaxo Smith Kline [Member]	'	'
Operations [Line Items]	'	'
Percent of royalty on net sale	3.00%	'
Minimum [Member]	'	'
Operations [Line Items]	'	'
Operating Cycle	'364 days	'
Maximum [Member]	'	'
Operations [Line Items]	'	'
Operating Cycle	'371 days	'

Restructurings_Narrative_Detai

Restructurings (Narrative) (Details) (USD $)	3 Months Ended		12 Months Ended	49 Months Ended
	Mar. 31, 2014	Mar. 31, 2013	Dec. 31, 2013	Mar. 31, 2014	Dec. 31, 2012
	employee			restructuring
				employee
Restructuring Cost and Reserve [Line Items]	'	'	'	'	'
Number of restructurings implemented	'	'	'	5	'
Aggregate reduction in headcount	429	'	'	429	'
Restructuring charge (credit)	$46,000	$119,000	$1,231,000	$53,300,000	'
Restructuring reserve	12,231,000	'	13,472,000	12,231,000	19,222,000
Expected additional payment for restructuring	2,500,000	'	'	'	'
Restructuring reserve, settled with cash	1,409,000	'	6,765,000	36,600,000	'
Proceeds from subtenants	'	'	'	11,300,000	'
Proceeds from sale of property and equipment	276,000	0	'	'	'
Restructuring reserve, cash settlement net of proceeds	1,200,000	2,400,000	'	'	'
Facility Closing [Member]	'	'	'	'	'
Restructuring Cost and Reserve [Line Items]	'	'	'	'	'
Restructuring charge (credit)	159,000	'	662,000	29,400,000	'
Restructuring reserve	12,225,000	'	13,460,000	12,225,000	19,202,000
Restructuring reserve, settled with cash	1,403,000	'	6,331,000	'	'
Termination Benefits [Member]	'	'	'	'	'
Restructuring Cost and Reserve [Line Items]	'	'	'	'	'
Restructuring charge (credit)	'	'	'	21,700,000	'
Asset Impairment [Member]	'	'	'	'	'
Restructuring Cost and Reserve [Line Items]	'	'	'	'	'
Restructuring charge (credit)	-100,000	'	'	2,200,000	'
Proceeds from sale of property and equipment	'	'	'	$2,900,000	'

Restructurings_Summary_of_Comp

Restructurings (Summary of Components of Restructuring Liability) (Details) (USD $)	3 Months Ended		12 Months Ended	49 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013	Dec. 31, 2013	Mar. 31, 2014
Restructuring Reserve [Roll Forward]	'	'	'	'
Restructuring liability	$13,472	$19,222	$19,222	'
Restructuring charge (credit)	46	119	1,231	53,300
Cash payments	-1,409	'	-6,765	-36,600
Adjustments or non-cash credits	-77	'	-311	'
Proceeds from sale of assets	199	'	95	'
Restructuring liability	12,231	'	13,472	12,231
Facility Charges [Member]	'	'	'	'
Restructuring Reserve [Roll Forward]	'	'	'	'
Restructuring liability	13,460	19,202	19,202	'
Restructuring charge (credit)	159	'	662	29,400
Cash payments	-1,403	'	-6,331	'
Adjustments or non-cash credits	9	'	-73	'
Proceeds from sale of assets	0	'	0	'
Restructuring liability	12,225	'	13,460	12,225
Other [Member]	'	'	'	'
Restructuring Reserve [Roll Forward]	'	'	'	'
Restructuring liability	12	20	20	'
Restructuring charge (credit)	-113	'	569	'
Cash payments	-6	'	-434	'
Adjustments or non-cash credits	-86	'	-238	'
Proceeds from sale of assets	199	'	95	'
Restructuring liability	$6	'	$12	$6

Cash_and_Investments_Cash_and_1

Cash and Investments Cash and Investments (Details) (USD $)	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013	Dec. 31, 2013
	account
	affiliate
	investment
Schedule of Available-for-sale Securities [Line Items]	'	'	'
Amortized Cost	$407,489,000	'	$415,617,000
Gross Unrealized Gains	286,000	'	300,000
Gross Unrealized Losses	-26,000	'	-55,000
Fair Value	407,749,000	'	415,862,000
Debt collateral, number of required investment accounts	1	'	'
Debt collateral, number of affiliate banks	1	'	'
Amortized Cost	406,755,000	'	409,721,000
Gross Unrealized Gains	286,000	'	300,000
Gross Unrealized Losses	-26,000	'	-55,000
Fair Value	407,015,000	'	409,966,000
Gain (loss) on sale of investments	0	0	'
Number of investments in an unrealized loss position, less than 1 year	27	'	'
Unrealized loss position, less than 1 year	39,500,000	'	'
Number of investments in an unrealized loss position, greater than 1 year	0	'	'
Unrealized loss position, greater than 1 year	0	'	'
Mature within One Year	358,595,000	'	'
After One Year through Two Years	48,420,000	'	'
Money market funds [Member]	'	'	'
Schedule of Available-for-sale Securities [Line Items]	'	'	'
Amortized Cost	71,150,000	'	24,813,000
Gross Unrealized Gains	0	'	0
Gross Unrealized Losses	0	'	0
Fair Value	71,150,000	'	24,813,000
Mature within One Year	71,150,000	'	'
After One Year through Two Years	0	'	'
Commercial paper [Member]	'	'	'
Schedule of Available-for-sale Securities [Line Items]	'	'	'
Amortized Cost	103,273,000	'	94,682,000
Gross Unrealized Gains	0	'	0
Gross Unrealized Losses	0	'	0
Fair Value	103,273,000	'	94,682,000
Mature within One Year	103,273,000	'	'
After One Year through Two Years	0	'	'
Corporate bonds [Member]	'	'	'
Schedule of Available-for-sale Securities [Line Items]	'	'	'
Amortized Cost	208,208,000	'	239,937,000
Gross Unrealized Gains	166,000	'	190,000
Gross Unrealized Losses	-26,000	'	-55,000
Fair Value	208,348,000	'	240,072,000
Mature within One Year	168,772,000	'	'
After One Year through Two Years	39,576,000	'	'
U.S. Treasury and government sponsored enterprises [Member]	'	'	'
Schedule of Available-for-sale Securities [Line Items]	'	'	'
Amortized Cost	21,372,000	'	44,284,000
Gross Unrealized Gains	116,000	'	102,000
Gross Unrealized Losses	0	'	0
Fair Value	21,488,000	'	44,386,000
Mature within One Year	15,400,000	'	'
After One Year through Two Years	6,088,000	'	'
Municipal bonds [Member]	'	'	'
Schedule of Available-for-sale Securities [Line Items]	'	'	'
Amortized Cost	2,752,000	'	6,005,000
Gross Unrealized Gains	4,000	'	8,000
Gross Unrealized Losses	0	'	'
Fair Value	2,756,000	'	6,013,000
Mature within One Year	0	'	'
After One Year through Two Years	2,756,000	'	'
Silicon Valley Bank Loan And Security Agreement [Member]	'	'	'
Schedule of Available-for-sale Securities [Line Items]	'	'	'
Collateral balance	83,200,000	'	83,700,000
Cash and cash equivalents [Member]	'	'	'
Schedule of Available-for-sale Securities [Line Items]	'	'	'
Amortized Cost	157,538,000	'	103,978,000
Gross Unrealized Gains	1,000	'	0
Gross Unrealized Losses	0	'	0
Fair Value	157,539,000	'	103,978,000
Short-term investments [Member]	'	'	'
Schedule of Available-for-sale Securities [Line Items]	'	'	'
Amortized Cost	115,931,000	'	138,403,000
Gross Unrealized Gains	119,000	'	94,000
Gross Unrealized Losses	-17,000	'	-22,000
Fair Value	116,033,000	'	138,475,000
Short-term restricted cash and investments [Member]	'	'	'
Schedule of Available-for-sale Securities [Line Items]	'	'	'
Amortized Cost	12,142,000	'	12,173,000
Gross Unrealized Gains	66,000	'	40,000
Gross Unrealized Losses	0	'	0
Fair Value	12,208,000	'	12,213,000
Long-term investments [Member]	'	'	'
Schedule of Available-for-sale Securities [Line Items]	'	'	'
Amortized Cost	111,110,000	'	144,226,000
Gross Unrealized Gains	54,000	'	106,000
Gross Unrealized Losses	-9,000	'	-33,000
Fair Value	111,155,000	'	144,299,000
Long-term restricted cash and investments [Member]	'	'	'
Schedule of Available-for-sale Securities [Line Items]	'	'	'
Amortized Cost	10,768,000	'	16,837,000
Gross Unrealized Gains	46,000	'	60,000
Gross Unrealized Losses	0	'	0
Fair Value	$10,814,000	'	$16,897,000

Inventory_Details

Inventory (Details) (USD $)	Mar. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Inventory Disclosure [Abstract]	'	'
Raw materials	$678	$529
Work in process	1,665	2,280
Finished goods	343	81
Total	$2,686	$2,890	[1]
[1]	The condensed consolidated balance sheet as of December 31, 2013 has been derived from the audited financial statements as of that date.

Debt_Schedule_Of_Debt_Details

Debt (Schedule Of Debt) (Details) (USD $)	Mar. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Debt Instrument [Line Items]	'	'
Total debt	$343,019	$347,237
Less: current portion	-1,392	-11,762
Long-term debt	341,627	335,475
Senior Subordinated Notes [Member] | Convertible Senior Subordinated Notes due 2019 [Member]	'	'
Debt Instrument [Line Items]	'	'
Convertible Debt	169,415	165,296
Secured Debt [Member] | Deerfield Notes [Member]	'	'
Debt Instrument [Line Items]	'	'
Convertible Debt	91,993	99,851
Term Loan [Member] | Silicon Valley Bank term loan and Line of Credit [Member]	'	'
Debt Instrument [Line Items]	'	'
Silicon Valley Bank term loan	80,000	80,000
Line of Credit [Member] | Silicon Valley Bank term loan and Line of Credit [Member]	'	'
Debt Instrument [Line Items]	'	'
Silicon Valley Bank Line of Credit	$1,611	$2,090

Debt_Narrative_Details

Debt (Narrative) (Details) (USD $)

Mar. 31, 2014

Jan. 22, 2014

Mar. 31, 2014

Mar. 31, 2014

Mar. 31, 2013

Dec. 31, 2013

Aug. 14, 2012

Mar. 31, 2014

Mar. 31, 2013

Jan. 22, 2014

Dec. 31, 2013

Jun. 30, 2010

Jan. 22, 2014

Jan. 22, 2014

Issued On January 22, 2014 [Member]

Issued On January 22, 2014 [Member]

Senior Subordinated Notes [Member]

Senior Subordinated Notes [Member]

Senior Subordinated Notes [Member]

Senior Subordinated Notes [Member]

Secured Convertible Notes Due June 2015 [Member]

Secured Convertible Notes Due June 2015 [Member]

Secured Convertible Notes Due June 2015 [Member]

Secured Convertible Notes Due June 2015 [Member]

Secured Convertible Notes Due June 2015 [Member]

Secured Convertible Notes Due June 2015 [Member]

Secured Convertible Notes Due June 2015 [Member]

4.25% Convertible Senior Subordinated Notes due August 15, 2019 [Member]

4.25% Convertible Senior Subordinated Notes due August 15, 2019 [Member]

4.25% Convertible Senior Subordinated Notes due August 15, 2019 [Member]

4.25% Convertible Senior Subordinated Notes due August 15, 2019 [Member]

Deerfield Financing [Member]

Deerfield Financing [Member]

Deerfield Financing [Member]

Deerfield Financing [Member]

Deerfield Financing [Member]

Deerfield Financing [Member]

Deerfield Financing [Member]

Coupon Interest [Member]

Payment-in-Kind Interest [Member]

Debt Instrument [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Debt, interest rate

'

'

'

'

'

'

4.25%

'

'

'

'

'

'

'

Debt, principal amount

'

'

'

$287,500,000

'

$287,500,000

$287,500,000

'

'

'

'

$124,000,000

'

'

Convertible debt

'

'

'

169,415,000

'

165,296,000

'

104,000,000

'

'

114,000,000

'

'

'

Interest expense, debt

'

'

'

7,400,000

7,000,000

'

'

4,200,000

3,900,000

'

'

'

'

'

Interest expense, coupon interest

'

'

'

3,100,000

3,100,000

'

'

'

'

'

'

'

'

'

Amortization of financing costs and discounts

'

'

'

4,300,000

3,900,000

'

'

2,700,000

2,400,000

'

'

'

'

'

Balance of unamortized closing fees and expenses

'

'

'

3,800,000

'

4,000,000

'

3,600,000

'

'

1,400,000

'

'

'

Principal eligible for extension option

'

'

'

'

'

'

'

'

'

100,000,000

'

'

'

'

Debt instrument, interest rate, stated percentage after extension option election

'

'

'

'

'

'

'

'

'

15.00%

'

'

7.50%

7.50%

Warrant period

'

'2 years

'

'

'

'

'

'

'

'

'

'

'

'

Warrants outstanding

2,186,362

1,000,000

1,000,000

'

'

'

'

'

'

'

'

'

'

'

Warrant exercise price (in dollars per warrant)

'

9.7

9.7

'

'

'

'

'

'

'

'

'

'

'

Debt instrument, discount

'

'

'

'

'

'

'

'

'

$2,800,000

'

'

'

'

Debt_2019_Notes_Details

Debt (2019 Notes) (Details) (Senior Subordinated Notes [Member], 4.25% Convertible Senior Subordinated Notes due August 15, 2019 [Member], USD $)	Mar. 31, 2014	Dec. 31, 2013	Aug. 14, 2012
Senior Subordinated Notes [Member] | 4.25% Convertible Senior Subordinated Notes due August 15, 2019 [Member]	'	'	'
Debt Instrument [Line Items]	'	'	'
Net carrying amount of the liability component	$169,415,000	$165,296,000	'
Unamortized discount of the liability component	118,085,000	122,204,000	'
Face amount	$287,500,000	$287,500,000	$287,500,000

Common_Stock_And_Warrants_Narr

Common Stock And Warrants (Narrative) (Details) (USD $)	1 Months Ended	3 Months Ended		0 Months Ended	3 Months Ended
	Jan. 31, 2014	Mar. 31, 2014	Mar. 31, 2013	Jan. 22, 2014	Mar. 31, 2014
				Issued On January 22, 2014 [Member]	Issued On January 22, 2014 [Member]
Class of Warrant or Right [Line Items]	'	'	'	'	'
Public offering of common stock	10,000,000	'	'	'	'
Share price (dollars per share)	$8	'	'	'	'
Net proceeds from public offering	$75,600,000	$75,646,000	$0	'	'
Warrant period	'	'	'	'2 years	'
Warrants outstanding	'	2,186,362	'	1,000,000	1,000,000
Warrant exercise price (in dollars per warrant)	'	'	'	9.7	9.7
Warrant repricing terms on exercise of extension option	'	'	'	120.00%	'
Fair value of warrants	'	'	'	2,800,000	1,000,000
Unrealized gain on warrants	'	'	'	'	$1,700,000

Common_Stock_And_Warrants_Sche

Common Stock And Warrants (Schedule Of Warrants To Purchase Common Stock Outstanding And Exercisable) (Details)	3 Months Ended
	Mar. 31, 2014	Jan. 22, 2014
Class of Warrant or Right [Line Items]	'	'
Number of Shares	2,186,362	'
Issued On June 4, 2008 [Member]	'	'
Class of Warrant or Right [Line Items]	'	'
Exercise Price per Share	7.4	'
Expiration Date	'6/4/2014	'
Number of Shares	1,000,000	'
Issued On June 10, 2009 [Member]	'	'
Class of Warrant or Right [Line Items]	'	'
Exercise Price per Share	6.05	'
Expiration Date	'6/10/2014	'
Number of Shares	186,362	'
Issued On January 22, 2014 [Member]	'	'
Class of Warrant or Right [Line Items]	'	'
Exercise Price per Share	9.7	9.7
Expiration Date	'1/22/2016	'
Number of Shares	1,000,000	1,000,000

Fair_Value_Measurements_Schedu

Fair Value Measurements (Schedule Of Fair Value Of Financial Assets Measured On A Recurring Basis) (Details) (USD $)	Mar. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Total fair value of financial assets	$407,015	$409,966
Warrants	1,022	'
Total financial liabilities	1,022	'
Level 1 [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Total fair value of financial assets	71,150	24,813
Warrants	0	'
Total financial liabilities	0	'
Level 2 [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Total fair value of financial assets	335,865	385,153
Warrants	0	'
Total financial liabilities	0	'
Level 3 [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Total fair value of financial assets	0	'
Warrants	1,022	'
Total financial liabilities	1,022	'
Money market funds [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Total fair value of financial assets	71,150	24,813
Money market funds [Member] | Level 1 [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Total fair value of financial assets	71,150	24,813
Money market funds [Member] | Level 2 [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Total fair value of financial assets	0	0
Money market funds [Member] | Level 3 [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Total fair value of financial assets	0	'
Commercial paper [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Total fair value of financial assets	103,273	94,682
Commercial paper [Member] | Level 1 [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Total fair value of financial assets	0	0
Commercial paper [Member] | Level 2 [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Total fair value of financial assets	103,273	94,682
Commercial paper [Member] | Level 3 [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Total fair value of financial assets	0	'
Corporate bonds [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Total fair value of financial assets	208,348	240,072
Corporate bonds [Member] | Level 1 [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Total fair value of financial assets	0	0
Corporate bonds [Member] | Level 2 [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Total fair value of financial assets	208,348	240,072
Corporate bonds [Member] | Level 3 [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Total fair value of financial assets	0	'
U.S. Treasury and government sponsored enterprises [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Total fair value of financial assets	21,488	44,386
U.S. Treasury and government sponsored enterprises [Member] | Level 1 [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Total fair value of financial assets	0	0
U.S. Treasury and government sponsored enterprises [Member] | Level 2 [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Total fair value of financial assets	21,488	44,386
U.S. Treasury and government sponsored enterprises [Member] | Level 3 [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Total fair value of financial assets	0	'
Municipal bonds [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Total fair value of financial assets	2,756	6,013
Municipal bonds [Member] | Level 1 [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Total fair value of financial assets	0	0
Municipal bonds [Member] | Level 2 [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Total fair value of financial assets	2,756	6,013
Municipal bonds [Member] | Level 3 [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Total fair value of financial assets	$0	'

Fair_Value_Measurements_Schedu1

Fair Value Measurements (Schedule of Estimated Fair Value of Outstanding Debt) (Details) (USD $)	Mar. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Carrying Amount [Member] | Senior Subordinated Notes [Member] | 2019 Notes [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Fair values of financial instruments	$169,415	$165,296
Carrying Amount [Member] | Term Loan [Member] | Silicon Valley Bank term loan and Line of Credit [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Fair values of financial instruments	80,000	80,000
Carrying Amount [Member] | Line of Credit [Member] | Silicon Valley Bank term loan and Line of Credit [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Fair values of financial instruments	1,611	2,090
Fair Value [Member] | Senior Subordinated Notes [Member] | 2019 Notes [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Fair values of financial instruments	255,731	339,883
Fair Value [Member] | Term Loan [Member] | Silicon Valley Bank term loan and Line of Credit [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Fair values of financial instruments	79,900	79,946
Fair Value [Member] | Line of Credit [Member] | Silicon Valley Bank term loan and Line of Credit [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Fair values of financial instruments	$1,611	$2,090

Fair_Value_Measurements_Schedu2

Fair Value Measurements (Schedule of Assumptions Used) (Details) (Issued On January 22, 2014 [Member], USD $)	0 Months Ended	3 Months Ended
In Thousands, unless otherwise specified	Jan. 22, 2014	Mar. 31, 2014
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]	'	'
Warrant period	'2 years	'
Warrant liability [Member]	'	'
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]	'	'
Fair value of warrants	$2,762	$1,022
Risk-free interest rate	0.95%	0.98%
Dividend yield	0.00%	0.00%
Volatility	57.00%	84.00%
Average expected life	'3 years 2 months 12 days	'3 years 0 months 7 days

StockBased_Compensation_Schedu

Stock-Based Compensation (Schedule of Allocated Employee Stock-Based Compensation Expenses) (Details) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]	'	'
Total employee stock-based compensation expense	$3,758	$2,675
Research and development expense [Member]	'	'
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]	'	'
Total employee stock-based compensation expense	1,565	1,407
Selling, general and administrative expense [Member]	'	'
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]	'	'
Total employee stock-based compensation expense	$2,193	$1,268

StockBased_Compensation_Schedu1

Stock-Based Compensation (Schedule of Fair Value of Employee Share-Based Payments Awards Estimated Using the Assumptions and Weighted Average Fair Values) (Details) (USD $)	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Stock Options [Member]	'	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'
Weighted average grant date fair value	$4.70	$2.45
Risk-free interest rate	1.59%	0.78%
Dividend yield	0.00%	0.00%
Volatility	81.00%	62.00%
Expected life	'5 years 6 months	'5 years 2 months 12 days
Employee Stock Purchase Plan [Member]	'	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'
Weighted average grant date fair value	$1.59	$1.59
Risk-free interest rate	0.08%	0.15%
Dividend yield	0.00%	0.00%
Volatility	62.00%	67.00%
Expected life	'6 months	'6 months

StockBased_Compensation_Narrat

Stock-Based Compensation (Narrative) (Details) (USD $)	Mar. 31, 2014	Dec. 31, 2013	Mar. 31, 2014	Sep. 30, 2013	Mar. 31, 2014	Mar. 31, 2014
In Millions, except Share data, unless otherwise specified			Performance Stock Options [Member]	Performance Stock Options [Member]	Stock Options [Member]	Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'	'	'	'	'
Options outstanding, in shares	24,232,154	23,983,275	3,720,752	'	'	'
Grant date fair value	'	'	'	$6.90	'	'
Unrecognized compensation expense	'	'	'	'	$26.60	$6.70
Unrecognized compensation expense, weighted-average period for recognition (in years)	'	'	'	'	'2 years 6 months 7 days	'3 years 2 months 4 days

StockBased_Compensation_Summar

Stock-Based Compensation (Summary of All Stock Option Activity) (Details) (USD $)	3 Months Ended
In Thousands, except Share data, unless otherwise specified	Mar. 31, 2014
Shares [Roll Forward]	'
Options outstanding at beginning of period, Shares	23,983,275
Granted, Shares	626,290
Exercised, Shares	-19,090
Forfeited, Shares	-5,979
Expired, Shares	-352,342
Options outstanding at end of period, Shares	24,232,154
Exercisable at end of period, Shares	14,057,195
Weighted Average Exercise Price [Roll Forward]	'
Options outstanding at beginning of period, Weighted Average Exercise Price	$6.48
Granted, Weighted Average Exercise Price	$6.96
Exercised, Weighted Average Exercise Price	$6.28
Forfeited, Weighted Average Exercise Price	$5.73
Expired, Weighted Average Exercise Price	$7.75
Options outstanding at end of period, Weighted Average Exercise Price	$6.47
Exercisable at end of period, Weighted Average Exercise Price	$7.12
Options outstanding at end of period, Weighted Average Remaining Contractual Term	'4 years 5 months 15 days
Exercisable at end of period, Weighted Average Remaining Contractual Term	'3 years 4 months 6 days
Options outstanding at end of period, Aggregate Intrinsic Value, in dollars	$2
Exercisable at end of period, Aggregate Intrinsic Value, in dollars	$2

StockBased_Compensation_Summar1

Stock-Based Compensation (Summary of All RSU Activity) (Details) (Restricted Stock Units (RSUs) [Member], USD $)	3 Months Ended
In Thousands, except Share data, unless otherwise specified	Mar. 31, 2014
Restricted Stock Units (RSUs) [Member]	'
Shares [Roll Forward]	'
RSUs outstanding at beginning of period, Shares	1,810,521
Awarded, Shares	32,096
Released, Shares	-81,590
Forfeited, Shares	-14,687
RSUs outstanding at end of period, Shares	1,746,340
Weighted Average Grant DateFair Value [Roll Forward]	'
RSUs outstanding at beginning of period, Weighted Average Grant Date Fair Value	$5.56
Awarded, Weighted Average Grant Date Fair Value	$6.77
Released, Weighted Average Grant Date Fair Value	$7.11
Forfeited, Weighted Average Grant Date Fair Value	$5.56
RSUs outstanding at end of period, Weighted Average Grant Date Fair Value	$5.51
RSUs outstanding at end of period, Weighted Average Remaining Contractual Term	'3 years 2 months 4 days
RSUs outstanding at end of period, Aggregate Intrinsic Value, in dollars	$5,903

Net_Loss_Per_Share_Details

Net Loss Per Share (Details) (USD $)	3 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]	'	'
Net loss, in dollars	($74,619)	($44,729)
Shares used in computing basic and diluted net loss per share	191,699	183,742
Net loss per share, basic and diluted, in dollars per share	($0.39)	($0.24)
Potentially dilutive shares	82,611	73,745
Convertible debt [Member]	'	'
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]	'	'
Potentially dilutive shares	54,123	54,123
Outstanding stock options, unvested RSUs and ESPP contributions [Member]	'	'
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]	'	'
Potentially dilutive shares	26,302	18,181
Warrants [Member]	'	'
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]	'	'
Potentially dilutive shares	2,186	1,441

Concentrations_of_Credit_Risk_1

Concentrations of Credit Risk (Details)	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Revenue from Rights Concentration Risk [Member] | Accounts Receivable [Member] | European Distribution Partner [Member]	'	'
Concentration Risk [Line Items]	'	'
Concentration Risk, Percentage	6.00%	'
Revenue from Rights Concentration Risk [Member] | Accounts Receivable [Member] | Diplomat Specialty Pharmacy [Member]	'	'
Concentration Risk [Line Items]	'	'
Concentration Risk, Percentage	70.00%	'
Revenue from Rights Concentration Risk [Member] | Revenue, Rights Granted [Member] | Bristol-Myers Squibb [Member]	'	'
Concentration Risk [Line Items]	'	'
Concentration Risk, Percentage	0.00%	81.00%
Revenue from Rights Concentration Risk [Member] | Revenue, Rights Granted [Member] | Diplomat Specialty Pharmacy [Member]	'	'
Concentration Risk [Line Items]	'	'
Concentration Risk, Percentage	98.00%	19.00%
Geographic Concentration Risk [Member] | Sales [Member] | UNITED STATES	'	'
Concentration Risk [Line Items]	'	'
Concentration Risk, Percentage	98.00%	100.00%