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[1]	The condensed consolidated balance sheet at December 31, 2011 has been derived from the audited consolidated financial statements at that date but does not include all of the information and footnotes required by U.S. generally accepted accounting principles for complete financial statements.

Consolidated Statements Of Other Comprehensive Loss - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2012	Mar. 31, 2011
Consolidated Statements Of Other Comprehensive Loss [Abstract]
Net loss	$ (26,151)	$ (27,490)
Net unrealized gains (losses) on available-for-sale securities	188	(43)
Comprehensive loss	$ (25,963)	$ (27,533)

- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Accounting Research Bulletin (ARB)
-Number 51
-Paragraph 8, 9, 10, 11, 12, 13, 14
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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Reference 3: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Research Bulletin (ARB)
-Number 51
-Paragraph A5
-Appendix A

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-Name Accounting Standards Codification
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-Name Accounting Standards Codification
-Glossary Net Income
-URI http://asc.fasb.org/extlink&oid=6518256

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-Name Accounting Standards Codification
-Glossary Other Comprehensive Income
-URI http://asc.fasb.org/extlink&oid=6519514

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-Name Accounting Standards Codification
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-Paragraph 3
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-Name Accounting Standards Codification
-Glossary Comprehensive Income
-URI http://asc.fasb.org/extlink&oid=6508144

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+ Details

- Definition

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Emerging Issues Task Force (EITF)
-Number 87-21
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Reference 3: http://www.xbrl.org/2003/role/presentationRef
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-Number 130
-Paragraph 10, 15
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-Name Regulation S-X (SX)
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-Name Regulation S-X (SX)
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-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=6519514

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Reference 16: http://www.xbrl.org/2003/role/presentationRef
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-Appendix A

+ Details

- Definition

Appreciation or loss in value (before reclassification adjustment) of the total of unsold securities during the period being reported on, net of tax. Reclassification adjustments include: (1) the unrealized holding gain (loss), net of tax, at the date of the transfer for a debt security from the held-to-maturity category transferred into the available-for-sale category. Also includes the unrealized gain (loss) at the date of transfer for a debt security from the available-for-sale category transferred into the held-to-maturity category; (2) the unrealized gains (losses) realized upon the sale of securities, after tax; and (3) the unrealized gains (losses) realized upon the write-down of securities, after tax.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 115
-Paragraph 13
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
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-Name Statement of Financial Accounting Standard (FAS)
-Number 130
-Paragraph 24
-Subparagraph b
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 3: http://www.xbrl.org/2003/role/presentationRef
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-Name Statement of Financial Accounting Standard (FAS)
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-Name Accounting Standards Codification
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-Name Accounting Standards Codification
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-Subparagraph (e)
-URI http://asc.fasb.org/extlink&oid=6920433&loc=d3e998-108581

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

+ Details

Stock-Based Compensation

3 Months Ended

Mar. 31, 2012

Stock-Based Compensation [Abstract]

Stock-Based Compensation

NOTE 2. Stock-Based Compensation

We recorded and allocated employee stock-based compensation expenses as follows (in thousands):


	Three Months Ended March 31,
	2012		2011
Research and development expense	$	1,207	$	1,748
General and administrative expense		1,097		1,332
Restructuring-related stock compensation expense		—		449

Total employee stock-based compensation expense	$	2,304	$	3,529

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 share-based payments awards was estimated using the following assumptions and weighted average fair values:


	Stock Options Three Months Ended March 31,					Employee Stock Purchase Plan Three Months Ended March 31,
	2012			2011 (1)		2012			2011
Weighted average grant date fair value	$	2.91		$	N/A	$	2.61		$	1.47
Risk-free interest rate		1.00	%		N/A		0.05	%		0.16	%
Dividend yield		0	%		N/A		0	%		0	%
Volatility		65	%		N/A		68	%		65	%
Expected life		5.2 years			N/A		0.5 years			0.5 years

(1)	No options were granted during the three months ended March 31, 2011.

A summary of all stock option activity for the three months ended March 31, 2012 is presented below:


	Shares			Weighted Average Exercise Price		Weighted Average Remaining Contractual Term		Aggregate Intrinsic Value
Options outstanding at December 31, 2011		17,436,378		$	7.16
Granted		66,175			5.26
Exercised		(22,031	)		4.97
Cancelled		(397,104	)		11.89

Options outstanding at March 31, 2012		17,083,418		$	7.04		4.69 years	$	617,036

Exercisable at March 31, 2012		13,278,874		$	7.38		4.15 years	$	502,674

As of March 31, 2012, $9.6 million of total unrecognized compensation expense related to employee stock options was expected to be recognized over a weighted-average period of 2.72 years.

A summary of all RSU activity for the three months ended March 31, 2012 is presented below:


	Shares			Weighted Average Grant Date Fair Value		Weighted Average Remaining Contractual Term		Aggregate Intrinsic Value
RSUs outstanding at December 31, 2011		1,391,691		$	6.92
Awarded		18,734			5.27
Released		(288,161	)		7.31
Forfeited		(18,387	)		7.45

RSUs outstanding at March 31, 2012		1,103,877		$	6.79		1.37 years	$	5,718,083

As of March 31, 2012, $5.7 million of total unrecognized compensation expense related to employee RSUs was expected to be recognized over a weighted-average period of 2.45 years.

- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 123R
-Paragraph 64, 65, A240
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Statement of Position (SOP)
-Number 93-6
-Paragraph 53
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Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Staff Accounting Bulletin (SAB)
-Number Topic 14

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
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-Section 50
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-Name Accounting Standards Codification
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+ Details

Stock-Based Compensation (Tables)

3 Months Ended

Mar. 31, 2012

Stock-Based Compensation [Abstract]

Schedule Of Allocated Employee Stock-Based Compensation Expenses


	Three Months Ended March 31,
	2012		2011
Research and development expense	$	1,207	$	1,748
General and administrative expense		1,097		1,332
Restructuring-related stock compensation expense		—		449

Total employee stock-based compensation expense	$	2,304	$	3,529

Schedule Of Fair Value Of Employee Share-Based Payments Awards Estimated Using The Assumptions And Weighted Average Fair Values


	Stock Options Three Months Ended March 31,					Employee Stock Purchase Plan Three Months Ended March 31,
	2012			2011 (1)		2012			2011
Weighted average grant date fair value	$	2.91		$	N/A	$	2.61		$	1.47
Risk-free interest rate		1.00	%		N/A		0.05	%		0.16	%
Dividend yield		0	%		N/A		0	%		0	%
Volatility		65	%		N/A		68	%		65	%
Expected life		5.2 years			N/A		0.5 years			0.5 years

(1)	No options were granted during the three months ended March 31, 2011.

Summary Of All Stock Option Activity


	Shares			Weighted Average Exercise Price		Weighted Average Remaining Contractual Term		Aggregate Intrinsic Value
Options outstanding at December 31, 2011		17,436,378		$	7.16
Granted		66,175			5.26
Exercised		(22,031	)		4.97
Cancelled		(397,104	)		11.89

Options outstanding at March 31, 2012		17,083,418		$	7.04		4.69 years	$	617,036

Exercisable at March 31, 2012		13,278,874		$	7.38		4.15 years	$	502,674

Summary Of All RSU Activity


	Shares			Weighted Average Grant Date Fair Value		Weighted Average Remaining Contractual Term		Aggregate Intrinsic Value
RSUs outstanding at December 31, 2011		1,391,691		$	6.92
Awarded		18,734			5.27
Released		(288,161	)		7.31
Forfeited		(18,387	)		7.45

RSUs outstanding at March 31, 2012		1,103,877		$	6.79		1.37 years	$	5,718,083

- Definition

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

+ References + Details

Stock-Based Compensation (Schedule Of Allocated Employee Stock-Based Compensation Expenses) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2012	Mar. 31, 2011
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total employee stock-based compensation expense	$ 2,304	$ 3,529
Research And Development Expense [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total employee stock-based compensation expense	1,207	1,748
General And Administrative Expense [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total employee stock-based compensation expense	$ 1,097	1,332
Restructuring-Related Stock Compensation Expense [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total employee stock-based compensation expense		$ 449

- Definition

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

+ References + Details

Stock-Based Compensation (Narrative) (Details) $ in Millions	3 Months Ended
	Mar. 31, 2012 USD ($)
Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total unrecognized compensation expense	$ 9.6
Unrecognized compensation expense, weighted-average period for recognition (in years)	2.72
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total unrecognized compensation expense	$ 5.7
Unrecognized compensation expense, weighted-average period for recognition (in years)	2.45

Organization And Summary Of Significant Accounting Policies (Schedule Of Available-For-Sale Securities) (Details) - USD ($) $ in Thousands	Mar. 31, 2012	Dec. 31, 2011
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale securities, Amortized Cost	$ 332,064	$ 283,858
Available-for-sale securities, Gross Unrealized Gains	96	36
Available-for-sale securities, Gross Unrealized Losses	(46)	(173)
Available-for-sale securities, Fair Value	332,114	283,721
Money Market Funds [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale securities, Amortized Cost	35,228	81,986
Available-for-sale securities, Gross Unrealized Gains
Available-for-sale securities, Gross Unrealized Losses
Available-for-sale securities, Fair Value	35,228	81,986
Commercial Paper [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale securities, Amortized Cost	96,753	29,079
Available-for-sale securities, Gross Unrealized Gains	18	2
Available-for-sale securities, Gross Unrealized Losses	(3)	(1)
Available-for-sale securities, Fair Value	96,768	29,080
Corporate Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale securities, Amortized Cost	110,795	116,068
Available-for-sale securities, Gross Unrealized Gains	65	22
Available-for-sale securities, Gross Unrealized Losses	(40)	(169)
Available-for-sale securities, Fair Value	110,820	115,921
U.S. Government Sponsored Enterprises [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale securities, Amortized Cost	65,638	37,237
Available-for-sale securities, Gross Unrealized Gains	13	12
Available-for-sale securities, Gross Unrealized Losses	(2)
Available-for-sale securities, Fair Value	65,649	37,249
Municipal Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale securities, Amortized Cost	23,650	19,488
Available-for-sale securities, Gross Unrealized Gains
Available-for-sale securities, Gross Unrealized Losses	(1)	(3)
Available-for-sale securities, Fair Value	23,649	19,485
Cash Equivalents [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale securities, Amortized Cost	70,465	74,256
Available-for-sale securities, Gross Unrealized Gains	1	1
Available-for-sale securities, Gross Unrealized Losses
Available-for-sale securities, Fair Value	70,466	74,257
Marketable Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale securities, Amortized Cost	172,930	120,143
Available-for-sale securities, Gross Unrealized Gains	95	35
Available-for-sale securities, Gross Unrealized Losses	(46)	(173)
Available-for-sale securities, Fair Value	172,979	120,005
Restricted Cash And Investments [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale securities, Amortized Cost	4,199	4,199
Available-for-sale securities, Gross Unrealized Gains
Available-for-sale securities, Gross Unrealized Losses
Available-for-sale securities, Fair Value	4,199	4,199
Long-Term Investments [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale securities, Amortized Cost	84,470	85,260
Available-for-sale securities, Gross Unrealized Gains
Available-for-sale securities, Gross Unrealized Losses
Available-for-sale securities, Fair Value	$ 84,470	$ 85,260

Organization And Summary Of Significant Accounting Policies (Policy)

3 Months Ended

Mar. 31, 2012

Organization And Summary Of Significant Accounting Policies [Abstract]

Organization

Organization

Exelixis, Inc. ("Exelixis," "we," "our" or "us") is a biotechnology company committed to developing small molecule therapies for the treatment of cancer. We are focusing our proprietary resources and development efforts exclusively on cabozantinib (XL184), our most advanced product candidate, in order to maximize the therapeutic and commercial potential of this compound. We believe cabozantinib has the potential to be a high-quality, broadly active, differentiated pharmaceutical product that can make a meaningful difference in the lives of patients. We have also established a portfolio of other novel compounds that we believe have the potential to address serious unmet medical needs, many of which are being advanced by partners as part of collaborations.

Basis Of Presentation

Basis of Presentation

The accompanying unaudited condensed 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 ("GAAP") for complete financial statements. In our opinion, all adjustments (consisting 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. Certain reclassifications of prior period amounts have been made to our condensed consolidated financial statements to conform to the current period presentation.

Exelixis adopted a 52- or 53-week fiscal year that ends on the Friday closest to December 31^st. Fiscal year 2011, a 52-week year, ended on December 30, 2011, and fiscal year 2012, a 52-week year, will end on December 28, 2012. For convenience, references in this report as of and for the fiscal quarters ended April 1, 2011 and March 30, 2012, and as of the fiscal year ended December 30, 2011, are indicated as ended March 31, 2011 and 2012, and as ended December 31, 2011, respectively.

Operating results for the three-month period ended March 31, 2012 are not necessarily indicative of the results that may be expected for the fiscal year ending December 28, 2012 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 fiscal year ended December 30, 2011 included in our Annual Report on Form 10-K filed with the SEC on February 22, 2012.

Basis Of Consolidation

Basis of Consolidation

The consolidated financial statements include the accounts of Exelixis and those of our wholly-owned subsidiaries. All intercompany balances and transactions have been eliminated.

Use Of Estimates

Use of Estimates

The preparation of the consolidated financial statements is in conformity with GAAP, which requires management to make 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 revenue recognition, clinical trial accruals, restructuring liability and stock option valuation. We base our estimates on historical experience and on various other market-specific and other relevant assumptions that are believed 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.

Cash And Investments

Cash and Investments

We consider all highly liquid investments purchased with an original maturity of three months or less to be cash equivalents. We invest in high-grade, short-term commercial paper and money market funds, which are subject to minimal credit and market risk.

All marketable securities are classified as available-for-sale and are carried at fair value. We view our available-for-sale portfolio as available for use in current operations. Accordingly, we have classified certain investments as short-term marketable securities, even though the stated maturity date may be one year or more beyond the current balance sheet date. Available-for-sale securities are stated at fair value based upon quoted market prices of the securities. We have classified certain investments as cash and cash equivalents or marketable securities that collateralize loan balances; however, they are not restricted to withdrawal. Funds that are used to collateralize equipment lines of credit that extend for over 12 months have been classified as long-term investments, in association with the loan arrangement. Unrealized gains and losses on available-for-sale investments are reported as a separate component of stockholders' equity. Realized gains and losses, net, and interest and dividends on available-for-sale securities are recorded in our Condensed Consolidated Statement of Operations as Interest income and other, net. The cost of securities sold is based on the specific identification method.

All of our marketable securities are subject to quarterly reviews for impairment that is deemed to be other-than-temporary. An investment is considered other-than-temporarily impaired when its fair value is below its amortized cost and (1) we intend to sell the security, (2) it is "more likely than not" that we will be required to sell the security before recovery of its amortized cost basis or (3) the present value of expected cash flows from the investment is not expected to recover the entire amortized cost basis.

The following summarizes available-for-sale securities as of March 31, 2012 (in thousands):


	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Fair Value
Money market funds	$	35,228	$	—	$	—		$	35,228
Commercial paper		96,753		18		(3	)		96,768
Corporate bonds		110,795		65		(40	)		110,820
U.S. Government sponsored enterprises		65,638		13		(2	)		65,649
Municipal bonds		23,650		—		(1	)		23,649

Total	$	332,064	$	96	$	(46	)	$	332,114


	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Fair Value
As reported:
Cash equivalents	$	70,465	$	1	$	—		$	70,466
Marketable securities		172,930		95		(46	)		172,979
Restricted cash and investments		4,199		—		—			4,199
Long-term investments		84,470		—		—			84,470

Total	$	332,064	$	96	$	(46	)	$	332,114

As of March 31, 2012, all securities that were in an unrealized loss position have been so for less than one year and the unrealized losses were due to market conditions and were not attributed to credit risk. Based on the scheduled maturities of our marketable securities, 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 available-for-sale securities as of December 31, 2011 (in thousands):


	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Fair Value
Money market funds	$	81,986	$	—	$	—		$	81,986
Commercial paper		29,079		2		(1	)		29,080
Corporate bonds		116,068		22		(169	)		115,921
U.S. Government sponsored enterprises		37,237		12		—			37,249
Municipal bonds		19,488		—		(3	)		19,485

Total	$	283,858	$	36	$	(173	)	$	283,721


	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Fair Value
As reported:
Cash equivalents	$	74,256	$	1	$	—		$	74,257
Marketable securities		120,143		35		(173	)		120,005
Restricted cash and investments		4,199		—		—			4,199
Long-term investments		85,260		—		—			85,260

Total	$	283,858	$	36	$	(173	)	$	283,721

The following summarizes available-for-sale securities as of March 31, 2012 by contractual maturity (in thousands):


	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Fair Value
Mature in less than one year	$	311,877	$	89	$	(40	)	$	311,926
Mature in one to two years		20,187		7		(6	)		20,188

Total	$	332,064	$	96	$	(46	)	$	332,114

The following summarizes available-for-sale securities as of December 31, 2011 by contractual maturity (in thousands):


	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Fair Value
Mature in less than one year	$	259,209	$	24	$	(151	)	$	259,082
Mature in one to two years		24,649		12		(22	)		24,639

Total	$	283,858	$	36	$	(173	)	$	283,721

Fair Value Measurements

Fair Value Measurements

The fair value of our financial instruments reflects the amounts that would be received upon sale of an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date (exit price). The fair value hierarchy has the following three levels:

Level 1—quoted prices in active markets for identical assets and liabilities.

Level 2—observable inputs other than quoted prices in active markets for identical assets and liabilities.

Level 3—unobservable inputs.

Our financial instruments are valued using quoted prices in active markets or based upon other observable inputs. The Level 2 inputs were determined using prices from independent pricing services based on quoted prices in active markets for similar instruments or on industry models using data inputs, such as interest rates and prices that can be directly observed or corroborated in active markets. There were no transfers between Level 1 and Level 2 of the fair value hierarchy, as determined at the end of each reporting period. The following table sets forth the fair value of our financial assets that were measured on a recurring basis as of March 31, 2012 and December 31, 2011, respectively (in thousands):

As of March 31, 2012:


	Level 1		Level 2		Level 3		Total
Money market funds	$	35,228	$	—	$	—	$	35,228
Commercial paper		—		96,768		—		96,768
Corporate bonds		—		110,820		—		110,820
U.S. Government sponsored agencies		—		65,649		—		65,649
Municipal bonds		—		23,649		—		23,649

Total	$	35,228	$	296,886	$	—	$	332,114

As of December 31, 2011:


	Level 1		Level 2		Level 3		Total
Money market funds	$	81,986	$	—	$	—	$	81,986
Commercial paper		—		29,080		—		29,080
Corporate bonds		—		115,921		—		115,921
U.S. Government sponsored agencies		—		37,249		—		37,249
Municipal bonds		—		19,485		—		19,485

Total	$	81,986	$	201,735	$	—	$	283,721

We have estimated the fair value of our long-term 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. However, due to the unique structure of our 2010 financing agreement with entities affiliated with Deerfield Management Company L.P. ("Deerfield") and the current non-liquid market in structured notes, there is no practicable method to determine the fair value of this instrument. See "Management's Discussion and Analysis of Financial Condition and Results of Operations—Liquidity and Capital Resources—Cash Requirements" for details on the structure and terms of our 2010 financing with Deerfield. The estimated fair value of our outstanding debt, excluding our 2010 financing with Deerfield, was as follows (in thousands):


	March 31, 2012		December 31, 2011
Equipment lines of credit	$	8,430	$	10,066
Silicon Valley Bank loan		77,884		77,835

Total	$	86,314	$	87,901

At March 31, 2012 and December 31, 2011, the book value of our debt outstanding, including our 2010 financing with Deerfield, was $182.1 million and $181.5 million, respectively. Our payment commitments associated with these debt instruments are fixed during the corresponding terms and comprise interest payments, principal payments or a combination thereof. The fair value of our debt will fluctuate with movements of interest rates, increasing in periods of declining rates of interest, and declining in periods of increasing rates of interest.

Long Lived Assets

Long Lived Assets

The carrying value of our long-lived assets is reviewed for impairment whenever events or changes in circumstances indicate that the asset may not be recoverable. An impairment loss would be recognized when estimated future cash flows expected to result from the use of the asset and its eventual disposition are less than its carrying amount. Long-lived assets include property and equipment and identified intangible assets. In the quarters ended March 31, 2012 and March 31, 2011, we recorded impairment charges associated with our property and equipment in the amount of approximately $0.2 million and $0.1 million, respectively, in connection with our 2010 and 2011 restructurings. See Note 4 to the Condensed Consolidated Financial Statements for further information on the restructurings.

Concentration Of Credit Risk

Concentration of Credit Risk

Financial instruments that potentially subject us to concentrations of credit risk are primarily cash and cash equivalents, accounts receivable and investments in marketable securities. Cash equivalents and marketable securities consist of money market funds, taxable commercial paper, corporate bonds with high credit quality, obligations of U.S. government sponsored enterprises and municipal bonds. All cash and cash equivalents and marketable securities are maintained with financial institutions that management believes are creditworthy. Other receivables are typically 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.

Net Loss Per Share

Net Loss Per Share

Basic and diluted net loss per share are computed by dividing net loss for the period by the weighted average number of shares of common stock outstanding during the period. The calculation of diluted net loss per share excludes potential common stock because its effect is antidilutive. Potential common stock consists of incremental common shares issuable (1) upon the exercise of stock options and warrants, (2) in connection with vesting of restricted stock units ("RSUs"), (3) pursuant to our employee stock purchase plan, and (4) upon conversion of our loan with GlaxoSmithKline, which was fully repaid in 2011.

As of March 31, 2012 and 2011, our potential common stock includes the following shares, all of which have been excluded from the computation of diluted net loss per share because their impact is antidilutive:


	March 31, 2012		March 31, 2011
Restricted stock units, common stock options and employee stock purchase plan		18,381,935		19,767,091
Conversion of loan		—		3,153,729
Warrants		1,441,215		2,250,000

Total antidilutive shares		19,823,150		25,170,820

Collaboration Arrangements

Collaboration Arrangements

Collaborative agreement reimbursement revenues are recorded as earned or owed based on the performance requirements by both parties under the respective contracts. For the quarter ended March 31, 2011, reimbursement payments were presented as collaboration reimbursement revenues. There were no such reimbursements for the quarter ended March 31, 2012, and we do not expect to record any further collaboration reimbursement revenues under our current collaborations.

Foreign Currency Translation And Remeasurement

Foreign Currency Translation and Remeasurement

Assets and liabilities denominated in currencies other than the functional currency are remeasured using exchange rates in effect at the end of the period and related gains or losses are recorded in interest income and other, net. Gains and losses on the remeasurement of foreign currency assets and liabilities were not material for the periods presented.

Recently Adopted Accounting Pronouncements

Recently Adopted Accounting Pronouncements

In December 2011, Accounting Standards Codification Topic 350, Testing Goodwill for Impairment was amended to allow the option of performing a qualitative assessment in evaluating goodwill for impairment. We adopted this guidance beginning January 1, 2012, and it did not have a material effect on our consolidated financial statements.

In May 2011, Accounting Standards Codification Topic 820, Fair Value Measurement was amended to converge U.S. and international accounting standards and provide more detailed disclosure. We adopted this guidance beginning January 1, 2012 and added additional disclosure as required. The amendment it did not have a material effect on our consolidated financial statements.

Recently Issued Accounting Pronouncements

Recently Issued Accounting Pronouncements

In December 2011, Accounting Standards Codification Topic 210, Balance Sheet was amended to converge U.S. and international accounting standards, and requires additional disclosure about offsetting of financial instruments. This guidance will be effective January 1, 2013 and we are evaluating the effect on our consolidated financial statements.

Organization And Summary Of Significant Accounting Policies (Schedule Of Estimated Fair Value Of Outstanding Debt) (Details) - USD ($) $ in Thousands	Mar. 31, 2012	Dec. 31, 2011
Debt Instrument [Line Items]
Fair value of outstanding debt	$ 86,314	$ 87,901
Equipment Lines Of Credit [Member]
Debt Instrument [Line Items]
Fair value of outstanding debt	8,430	10,066
Silicon Valley Bank Loan [Member]
Debt Instrument [Line Items]
Fair value of outstanding debt	$ 77,884	$ 77,835

Organization And Summary Of Significant Accounting Policies (Tables)

3 Months Ended

Mar. 31, 2012

Organization And Summary Of Significant Accounting Policies [Abstract]

Schedule Of Available-For-Sale Securities


	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Fair Value
Money market funds	$	35,228	$	—	$	—		$	35,228
Commercial paper		96,753		18		(3	)		96,768
Corporate bonds		110,795		65		(40	)		110,820
U.S. Government sponsored enterprises		65,638		13		(2	)		65,649
Municipal bonds		23,650		—		(1	)		23,649

Total	$	332,064	$	96	$	(46	)	$	332,114


	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Fair Value
As reported:
Cash equivalents	$	70,465	$	1	$	—		$	70,466
Marketable securities		172,930		95		(46	)		172,979
Restricted cash and investments		4,199		—		—			4,199
Long-term investments		84,470		—		—			84,470

Total	$	332,064	$	96	$	(46	)	$	332,114


	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Fair Value
Money market funds	$	81,986	$	—	$	—		$	81,986
Commercial paper		29,079		2		(1	)		29,080
Corporate bonds		116,068		22		(169	)		115,921
U.S. Government sponsored enterprises		37,237		12		—			37,249
Municipal bonds		19,488		—		(3	)		19,485

Total	$	283,858	$	36	$	(173	)	$	283,721


	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Fair Value
As reported:
Cash equivalents	$	74,256	$	1	$	—		$	74,257
Marketable securities		120,143		35		(173	)		120,005
Restricted cash and investments		4,199		—		—			4,199
Long-term investments		85,260		—		—			85,260

Total	$	283,858	$	36	$	(173	)	$	283,721

Summary Of Available-For-Sale Securities By Contractual Maturity

	Amortized Cost			Gross Unrealized Gains			Gross Unrealized Losses				Fair Value
Mature in less than one year		$	311,877		$	89		$	(40	)		$	311,926
Mature in one to two years			20,187			7			(6	)			20,188

Total		$	332,064		$	96		$	(46	)		$	332,114

	Amortized Cost			Gross Unrealized Gains			Gross Unrealized Losses				Fair Value
Mature in less than one year		$	259,209		$	24		$	(151	)		$	259,082
Mature in one to two years			24,649			12			(22	)			24,639

Total		$	283,858		$	36		$	(173	)		$	283,721

Schedule Of Fair Value Of Financial Assets Measured On A Recurring Basis

As of March 31, 2012:


	Level 1		Level 2		Level 3		Total
Money market funds	$	35,228	$	—	$	—	$	35,228
Commercial paper		—		96,768		—		96,768
Corporate bonds		—		110,820		—		110,820
U.S. Government sponsored agencies		—		65,649		—		65,649
Municipal bonds		—		23,649		—		23,649

Total	$	35,228	$	296,886	$	—	$	332,114

As of December 31, 2011:


	Level 1		Level 2		Level 3		Total
Money market funds	$	81,986	$	—	$	—	$	81,986
Commercial paper		—		29,080		—		29,080
Corporate bonds		—		115,921		—		115,921
U.S. Government sponsored agencies		—		37,249		—		37,249
Municipal bonds		—		19,485		—		19,485

Total	$	81,986	$	201,735	$	—	$	283,721

Schedule Of Estimated Fair Value Of Outstanding Debt


	March 31, 2012		December 31, 2011
Equipment lines of credit	$	8,430	$	10,066
Silicon Valley Bank loan		77,884		77,835

Total	$	86,314	$	87,901

Schedule Of Potential Shares Of Common Stock Excluded From Computation Of Diluted Net Loss Per Share


	March 31, 2012		March 31, 2011
Restricted stock units, common stock options and employee stock purchase plan		18,381,935		19,767,091
Conversion of loan		—		3,153,729
Warrants		1,441,215		2,250,000

Total antidilutive shares		19,823,150		25,170,820

- Definition

Tabular disclosure of available-for-sale securities which consist of all investments in certain debt and equity securities neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Emerging Issues Task Force (EITF)
-Number 03-1
-Paragraph 21
-Subparagraph a, b
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name FASB Staff Position (FSP)
-Number FAS115-1/124-1
-Paragraph 17
-Subparagraph a, b
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 115
-Paragraph 19, 20, 21
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=6872113&loc=d3e27337-111563

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=6872113&loc=d3e27198-111563

Reference 6: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6872113&loc=d3e27161-111563

Reference 7: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 320
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6957658&loc=d3e62557-112803

Reference 8: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 9
-URI http://asc.fasb.org/extlink&oid=6872113&loc=d3e27357-111563

Reference 9: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=6872113&loc=d3e27290-111563

Reference 10: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 320
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=6957658&loc=d3e62586-112803

+ Details

- Definition

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

+ References + Details

- Definition

Tabular disclosure of liabilities, including [financial] instruments measured at fair value that are classified in stockholders' equity, if any, by class that are measured at fair value on a recurring basis. The disclosures contemplated herein include the fair value measurements at the reporting date by the level within the fair value hierarchy in which the fair value measurements in their entirety fall, segregating fair value measurements using quoted prices in active markets for identical assets (Level 1), significant other observable inputs (Level 2), and significant unobservable inputs (Level 3). Where the quoted price in an active market for the identical liability is not available, the Level 1 input is the quoted price of an identical liability when traded as an asset.

+ References + Details

Document And Entity Information - shares	3 Months Ended
Document And Entity Information - shares	Mar. 31, 2012	Apr. 27, 2012
Document And Entity Information [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Mar. 30, 2012
Document Fiscal Year Focus	2012
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	--12-28
Entity Common Stock, Shares Outstanding		148,476,783

Sale Of Shares Of Common Stock (Details) - USD ($) $ in Thousands, shares in Millions	1 Months Ended		3 Months Ended
	Feb. 29, 2012	Mar. 31, 2011	Mar. 31, 2012	Mar. 31, 2011
Sale Of Shares Of Common Stock [Abstract]
Public offering of common stock	12.7	17.3
Net proceeds from public offering	$ 65,000	$ 179,300	$ 64,990	$ 179,347

Organization And Summary Of Significant Accounting Policies (Schedule Of Fair Value Of Financial Assets Measured On A Recurring Basis) (Details) - USD ($) $ in Thousands	Mar. 31, 2012	Dec. 31, 2011
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total fair value of financial assets	$ 332,114	$ 283,721
Money Market Funds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total fair value of financial assets	35,228	81,986
Commercial Paper [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total fair value of financial assets	96,768	29,080
Corporate Bonds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total fair value of financial assets	110,820	115,921
U.S. Government Sponsored Enterprises [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total fair value of financial assets	65,649	37,249
Municipal Bonds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total fair value of financial assets	23,649	19,485
Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total fair value of financial assets	35,228	81,986
Level 1 [Member] \| Money Market Funds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total fair value of financial assets	35,228	81,986
Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total fair value of financial assets	296,886	201,735
Level 2 [Member] \| Commercial Paper [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total fair value of financial assets	96,768	29,080
Level 2 [Member] \| Corporate Bonds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total fair value of financial assets	110,820	115,921
Level 2 [Member] \| U.S. Government Sponsored Enterprises [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total fair value of financial assets	65,649	37,249
Level 2 [Member] \| Municipal Bonds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total fair value of financial assets	$ 23,649	$ 19,485

Condensed Consolidated Balance Sheets (Parenthetical) - $ / shares	Mar. 31, 2012	Dec. 31, 2011
Condensed Consolidated Balance Sheets [Abstract]
Common stock, par value	$ 0.001	$ 0.001
Common stock, shares authorized	200,000,000	200,000,000
Common stock, shares issued	148,457,650	135,563,735
Common stock, shares outstanding	148,457,650	135,563,735

Organization And Summary Of Significant Accounting Policies

3 Months Ended

Mar. 31, 2012

Organization And Summary Of Significant Accounting Policies [Abstract]

Organization And Summary Of Significant Accounting Policies

NOTE 1. Organization and Summary of Significant Accounting Policies

Organization

Basis of Presentation

Basis of Consolidation

The consolidated financial statements include the accounts of Exelixis and those of our wholly-owned subsidiaries. All intercompany balances and transactions have been eliminated.

Use of Estimates

Cash and Investments

The following summarizes available-for-sale securities as of March 31, 2012 (in thousands):


	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Fair Value
Money market funds	$	35,228	$	—	$	—		$	35,228
Commercial paper		96,753		18		(3	)		96,768
Corporate bonds		110,795		65		(40	)		110,820
U.S. Government sponsored enterprises		65,638		13		(2	)		65,649
Municipal bonds		23,650		—		(1	)		23,649

Total	$	332,064	$	96	$	(46	)	$	332,114


	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Fair Value
As reported:
Cash equivalents	$	70,465	$	1	$	—		$	70,466
Marketable securities		172,930		95		(46	)		172,979
Restricted cash and investments		4,199		—		—			4,199
Long-term investments		84,470		—		—			84,470

Total	$	332,064	$	96	$	(46	)	$	332,114

The following summarizes available-for-sale securities as of December 31, 2011 (in thousands):


	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Fair Value
Money market funds	$	81,986	$	—	$	—		$	81,986
Commercial paper		29,079		2		(1	)		29,080
Corporate bonds		116,068		22		(169	)		115,921
U.S. Government sponsored enterprises		37,237		12		—			37,249
Municipal bonds		19,488		—		(3	)		19,485

Total	$	283,858	$	36	$	(173	)	$	283,721


	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Fair Value
As reported:
Cash equivalents	$	74,256	$	1	$	—		$	74,257
Marketable securities		120,143		35		(173	)		120,005
Restricted cash and investments		4,199		—		—			4,199
Long-term investments		85,260		—		—			85,260

Total	$	283,858	$	36	$	(173	)	$	283,721

The following summarizes available-for-sale securities as of March 31, 2012 by contractual maturity (in thousands):


	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Fair Value
Mature in less than one year	$	311,877	$	89	$	(40	)	$	311,926
Mature in one to two years		20,187		7		(6	)		20,188

Total	$	332,064	$	96	$	(46	)	$	332,114

The following summarizes available-for-sale securities as of December 31, 2011 by contractual maturity (in thousands):


	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Fair Value
Mature in less than one year	$	259,209	$	24	$	(151	)	$	259,082
Mature in one to two years		24,649		12		(22	)		24,639

Total	$	283,858	$	36	$	(173	)	$	283,721

Fair Value Measurements

Level 1—quoted prices in active markets for identical assets and liabilities.

Level 2—observable inputs other than quoted prices in active markets for identical assets and liabilities.

Level 3—unobservable inputs.

As of March 31, 2012:


	Level 1		Level 2		Level 3		Total
Money market funds	$	35,228	$	—	$	—	$	35,228
Commercial paper		—		96,768		—		96,768
Corporate bonds		—		110,820		—		110,820
U.S. Government sponsored agencies		—		65,649		—		65,649
Municipal bonds		—		23,649		—		23,649

Total	$	35,228	$	296,886	$	—	$	332,114

As of December 31, 2011:


	Level 1		Level 2		Level 3		Total
Money market funds	$	81,986	$	—	$	—	$	81,986
Commercial paper		—		29,080		—		29,080
Corporate bonds		—		115,921		—		115,921
U.S. Government sponsored agencies		—		37,249		—		37,249
Municipal bonds		—		19,485		—		19,485

Total	$	81,986	$	201,735	$	—	$	283,721


	March 31, 2012		December 31, 2011
Equipment lines of credit	$	8,430	$	10,066
Silicon Valley Bank loan		77,884		77,835

Total	$	86,314	$	87,901

Long Lived Assets

Concentration of Credit Risk

Net Loss Per Share


	March 31, 2012		March 31, 2011
Restricted stock units, common stock options and employee stock purchase plan		18,381,935		19,767,091
Conversion of loan		—		3,153,729
Warrants		1,441,215		2,250,000

Total antidilutive shares		19,823,150		25,170,820

Collaboration Arrangements

Foreign Currency Translation and Remeasurement

Recently Adopted Accounting Pronouncements

Recently Issued Accounting Pronouncements

Stock-Based Compensation (Schedule Of Fair Value Of Employee Share-Based Payments Awards Estimated Using The Assumptions And Weighted Average Fair Values) (Details)

3 Months Ended

Mar. 31, 2012

$ / shares

Mar. 31, 2011

$ / shares

Stock Options [Member]

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Weighted average grant date fair value | $ / shares

$ 2.91

^[1]

Risk-free interest rate

1.00%

^[1]

Dividend yield

0.00%

^[1]

Volatility

65.00%

^[1]

Expected life | yr

5.2

^[1]

Employee Stock Purchase Plan [Member]

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Weighted average grant date fair value | $ / shares

$ 2.61

$ 1.47

Risk-free interest rate

0.05%

0.16%

Dividend yield

0.00%

Volatility

68.00%

65.00%

Expected life | yr

0.5

[1]	No options were granted during the three months ended March 31, 2011.

Organization And Summary Of Significant Accounting Policies (Narrative) (Details) $ in Millions	3 Months Ended
	Mar. 31, 2012 USD ($)	Mar. 31, 2011 USD ($)	Dec. 31, 2011 USD ($)
Organization And Summary Of Significant Policies [Line Items]
Unrealized loss position of all securities in years	1
Book value of debt outstanding	$ 182.1		$ 181.5
2010 And 2011 Restructuring Plans [Member]
Organization And Summary Of Significant Policies [Line Items]
Amount written-down for property and equipment	$ 0.2	$ 0.1

Stock-Based Compensation (Summary Of All Stock Option Activity) (Details)	3 Months Ended
	Mar. 31, 2012 USD ($) $ / shares shares
Stock-Based Compensation [Abstract]
Options outstanding at December 31, 2011, Shares \| shares	17,436,378
Granted, Shares \| shares	66,175
Exercised, Shares \| shares	(22,031)
Cancelled, Shares \| shares	(397,104)
Options outstanding at March 31, 2012, Shares \| shares	17,083,418
Exercisable at March 31, 2012, Shares \| shares	13,278,874
Options outstanding at December 31, 2011, Weighted Average Exercise Price \| $ / shares	$ 7.16
Granted, Weighted Average Exercise Price \| $ / shares	5.26
Exercised, Weighted Average Exercise Price \| $ / shares	4.97
Cancelled, Weighted Average Exercise Price \| $ / shares	11.89
Options outstanding at March 31, 2012, Weighted Average Exercise Price \| $ / shares	7.04
Exercisable at March 31, 2012, Weighted Average Exercise Price \| $ / shares	$ 7.38
Options outstanding at March 31, 2012, Weighted Average Remaining Contractual Term, years	4.69
Exercisable at March 31, 2012, Weighted Average Remaining Contractual Term, years	4.15
Options outstanding at March 31, 2012, Aggregate Intrinsic Value \| $	$ 617,036,000
Exercisable at March 31, 2012, Aggregate Intrinsic Value \| $	$ 502,674,000

Restructurings (Tables)

3 Months Ended

Mar. 31, 2012

Restructurings [Abstract]

Summary Of Components Of Restructuring Liability


	Employee Severance And Other Benefits			Facility Charges			Asset Impairment			Legal and Other Fees		Total
Ending accrual balance as of December 31, 2011	$	6		$	13,921		$	—		$	51	$	13,978
Restructuring (credit) charge		(5	)		248			(438	)		—		(195	)
Cash payments		(1	)		(1,864	)		—			—		(1,865	)
Adjustments or non-cash credits		—			—			(409	)		—		(409	)
Proceeds from sale of assets		—			—			847			—		847

Ending accrual balance as of March 31, 2012	$	—		$	12,305		$	—		$	51	$	12,356

Organization And Summary Of Significant Accounting Policies (Schedule Of Potential Shares Of Common Stock Excluded From Computation Of Diluted Net Loss Per Share) (Details) - shares	3 Months Ended
	Mar. 31, 2012	Mar. 31, 2011
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total antidilutive shares	19,823,150	25,170,820
Restricted Stock Units, Common Stock Options And Employee Stock Purchase Plan [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total antidilutive shares	18,381,935	19,767,091
Conversion Of Loan [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total antidilutive shares		3,153,729
Warrants [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total antidilutive shares	1,441,215	2,250,000

- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 128
-Paragraph 13, 14
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 128
-Paragraph 171
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 128
-Paragraph 40
-Subparagraph c
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Diluted Earnings Per Share
-URI http://asc.fasb.org/extlink&oid=6510752

Reference 6: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Contingent Stock Agreement
-URI http://asc.fasb.org/extlink&oid=6508534

Reference 7: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Antidilution
-URI http://asc.fasb.org/extlink&oid=6505113

Reference 8: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Emerging Issues Task Force (EITF)
-Number 07-4
-Paragraph 4
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

+ Details

Condensed Consolidated Statements Of Operations - USD ($) shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2012	Mar. 31, 2011
Revenues:
Contract	$ 3,831	$ 12,410
License	14,679	22,789
Collaboration reimbursement		694
Total revenues	18,510	35,893
Operating expenses:
Research and development	33,096	45,691
General and administrative	7,905	9,165
Restructuring (credit) charge	(195)	4,767
Total operating expenses	40,806	59,623
Loss from operations	(22,296)	(23,730)
Other income (expense):
Interest income and other, net	160	183
Interest expense	(4,004)	(3,943)
Total other income (expense), net	(3,844)	(3,760)
Loss before income taxes	(26,140)	(27,490)
Income tax provision	(11)
Net loss	$ (26,151)	$ (27,490)
Net loss per share, basic and diluted	$ (0.18)	$ (0.24)
Shares used in computing basic and diluted loss per share amounts	141,940	113,215

Organization And Summary Of Significant Accounting policies (Summary Of Available-For-Sale Securities By Contractual Maturity) (Details) (b) - USD ($) $ in Thousands	Mar. 31, 2012	Dec. 31, 2011
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale securities, Amortized Cost	$ 332,064	$ 283,858
Available-for-sale securities, Gross Unrealized Gains	96	36
Available-for-sale securities, Gross Unrealized Losses	(46)	(173)
Available-for-sale securities, Fair Value	332,114	283,721
Mature In Less Than One Year [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale securities, Amortized Cost	311,877	259,209
Available-for-sale securities, Gross Unrealized Gains	89	24
Available-for-sale securities, Gross Unrealized Losses	(40)	(151)
Available-for-sale securities, Fair Value	311,926	259,082
Mature In One To Two Years [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale securities, Amortized Cost	20,187	24,649
Available-for-sale securities, Gross Unrealized Gains	7	12
Available-for-sale securities, Gross Unrealized Losses	(6)	(22)
Available-for-sale securities, Fair Value	$ 20,188	$ 24,639

- Definition

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

+ References + Details

Collaborations (Details) - USD ($) $ in Millions	1 Months Ended						3 Months Ended
Collaborations (Details) - USD ($) $ in Millions	Jan. 19, 2012	Dec. 31, 2011	Nov. 30, 2010	Dec. 31, 2008	Feb. 29, 2008	Jan. 31, 2007	Mar. 31, 2012
Merck [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Upfront cash payment	$ 12.0
Remaining unrecognized upfront payment							$ 10.7
Potential development and regulatory milestone payments							239.0
Maximum amount eligible for sales performance milestones							375.0
Deferred revenue recognized		$ 1.3
TGR5 License Agreement [Member] \| Bristol-Myers Squibb [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Upfront cash payment			$ 35.0
Maximum amount eligible for development and regulatory milestones			250.0
Maximum amount eligible for commercial milestones under collaborations agreement			150.0
Aggregate license revenue							17.1
ROR Collaboration Agreement [Member] \| Bristol-Myers Squibb [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Upfront cash payment			5.0
Maximum amount eligible for development and regulatory milestones			255.0
Maximum amount eligible for commercial milestones under collaborations agreement			150.0
Aggregate license revenue							$ 3.9
2007 Cancer Collaboration [Member] \| Bristol-Myers Squibb [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Upfront cash payment						$ 60.0
Selected milestone earnings entitled and received				$ 20.0	$ 20.0
Collaboration agreement opt-out consideration payment			$ 20.0

Collaborations	3 Months Ended
Collaborations	Mar. 31, 2012
Collaborations [Abstract]
Collaborations	NOTE 3. Collaborations Merck On December 21, 2011, we entered into an agreement with Merck & Co., Inc., known as MSD outside of the United States and Canada ("Merck"), pursuant to which we granted to Merck an exclusive worldwide license to our phosphoinositide-3 kinase delta ("PI3K-d") program, including XL499 and other related compounds. Pursuant to the terms of the agreement, Merck will have sole responsibility to research, develop, and commercialize compounds from our PI3K-d program. As a result we recognized $1.3 million in revenue in December 2011. Merck was required to pay us an up-front cash payment of $12.0 million in connection with the agreement, which we received on January 19, 2012. Under the terms of the agreement, we completed the transfer of the license and associated knowledge within ninety days of the effective date of the agreement and accordingly recognized the remaining unrecognized up-front payment of $10.7 million as of March 31, 2012. We will be eligible to receive potential development and regulatory milestone payments for multiple indications of up to $239.0 million. We will also be eligible to receive combined sales performance milestones of up to $375.0 million and royalties on net-sales of products emerging from the agreement. Milestones and royalties are payable on compounds emerging from our PI3K-d program or from certain compounds that arise from Merck's internal discovery efforts targeting PI3K-d during a certain period. Merck may at any time, upon specified prior notice to us, terminate the license. In addition, either of us may terminate the agreement for the other party's uncured material breach. In the event of termination by Merck at will or by us for Merck's uncured material breach, the license granted to Merck would terminate. In the event of a termination by us for Merck's uncured material breach, we would receive a royalty-free license from Merck to develop and commercialize certain joint products. In the event of termination by Merck for our uncured material breach, Merck would retain the licenses from us, and we would receive reduced royalties from Merck on commercial sales of products. Bristol-Myers Squibb Company *2007 Cancer Collaboration* In December 2006, we entered into a worldwide collaboration with Bristol-Myers Squibb Company ("Bristol-Myers Squibb"), which became effective in January 2007, to discover, develop and commercialize novel targeted therapies for the treatment of cancer. We were responsible for discovery and preclinical development of small molecule drug candidates directed against mutually selected targets. In January 2007, Bristol-Myers Squibb made an up-front payment of $60.0 million to us for which we granted Bristol-Myers Squibb the right to select up to three investigational new drug ("IND") candidates from six future Exelixis compounds. We recognized the up-front payment as revenues over the estimated research term. For each IND candidate selected, we were entitled to receive a $20.0 million selection milestone from Bristol-Myers Squibb. Once selected, Bristol-Myers Squibb became responsible for leading the further development and commercialization of the selected IND candidates. In addition, we had the right to opt in to co-promote the selected IND candidates, in which case we would equally share all development costs and profits in the United States. In January 2008 and November 2008, Bristol-Myers Squibb exercised its option under the collaboration to develop and commercialize XL139 (BMS-833923), a Hedgehog inhibitor, and XL413 (BMS-863233), a CDC7 inhibitor, respectively. Under the terms of the collaboration agreement, the selection of XL139 and XL413 by Bristol-Myers Squibb entitled us to milestone payments of $20.0 million each, which we received in February 2008 and December 2008, respectively. In addition, we exercised our option under the collaboration agreement to co-develop and co-commercialize each of XL139 and XL413 in the United States. In September 2010, we and Bristol-Myers Squibb terminated the XL413 program due to an unfavorable pharmacological profile observed in phase 1 clinical evaluation. Additionally, in connection with an amendment to the collaboration which became effective in November 2010, we exercised our right to opt-out of further co-development of XL139 in consideration for a payment of $20.0 million. This opt-out payment and the remaining deferred revenue balance as of the effective date of the opt-out, November 2010, were combined with and recognized in conjunction with the up-front fees received related to our TGR5 license agreement and ROR collaboration agreement entered into with Bristol-Myers Squibb in 2010, and will be recognized over the agreement with the longest term. Please refer to the "2010 Collaboration Agreements" within this note. The collaboration agreement was amended and restated in April 2011 in connection with an assignment of patents to one of our wholly-owned subsidiaries. We have no further responsibility for conducting new activities or funding new development or commercialization activities with respect to XL139 and will therefore no longer be eligible to share profits on sales of any commercialized products under the collaboration. We will continue to be eligible to receive regulatory and commercial milestones as well as double-digit royalties on any future sales of any products commercialized under the collaboration. As a result of the November 2010 amendment to the collaboration, the research term has ended, and we have no further obligation to deliver to Bristol-Myers Squibb a third IND candidate under the collaboration. *2010 Collaboration Agreements* TGR5 License Agreement In October 2010, we entered into a global license agreement with Bristol-Myers Squibb for XL475 (and any potential backups), a preclinical compound that modulates the metabolic target known as TGR5 (the "TGR5 License Agreement"). Pursuant to the terms of the TGR5 License Agreement, Bristol-Myers Squibb received a worldwide exclusive license to XL475 and has sole control and responsibility for all subsequent research, development, commercial and manufacturing activities. The TGR5 License Agreement became effective in November 2010 following clearance under the Hart-Scott-Rodino Antitrust Improvement Act of 1976, as amended. The license agreement was amended and restated in April 2011 in connection with an assignment of patents to one of our wholly-owned subsidiaries. Under the license agreement, Bristol-Myers Squibb received a worldwide exclusive license to XL475 and sole control and responsibility for all research, development, commercial and manufacturing activities. In November 2010 we received a nonrefundable up-front cash payment of $35.0 million from Bristol-Myers Squibb. Additionally, for each product developed by Bristol-Myers Squibb under the license, we will be eligible to receive development and regulatory milestones of up to $250.0 million and commercial milestones of up to $150.0 million, as well as royalties on commercial sales of any such products. As of March 31, 2012, we have recognized aggregate license revenue of $17.1 million under this agreement. ROR Collaboration Agreement In October 2010, we entered into a worldwide collaboration with Bristol-Myers Squibb pursuant to which each party granted to the other certain intellectual property licenses to enable the parties to discover, optimize and characterize ROR antagonists that may subsequently be developed and commercialized by Bristol-Myers Squibb. In November 2010 we received a nonrefundable up-front cash payment of $5.0 million from Bristol-Myers Squibb. Additionally, for each product developed by Bristol-Myers Squibb under the collaboration, we will be eligible to receive development and regulatory milestones of up to $255.0 million and commercial milestones of up to $150.0 million, as well as royalties on commercial sales of any such products. The collaboration agreement was amended and restated in April 2011 in connection with an assignment of patents to one of our wholly-owned subsidiaries. As of March 31, 2012, we have recognized aggregate license revenue of $3.9 million under this agreement.

Sale Of Shares Of Common Stock	3 Months Ended
Sale Of Shares Of Common Stock	Mar. 31, 2012
Sale Of Shares Of Common Stock [Abstract]
Sale Of Shares Of Common Stock	NOTE 5. Sale of Shares of Common Stock In March 2011, we completed a public offering of 17.3 million shares of our common stock pursuant to a shelf registration statement previously filed with the SEC, which the SEC declared effective on May 8, 2009. We received approximately $179.3 million in net proceeds from the offering after deducting the underwriting discount and related offering expenses. In February 2012, we completed a public offering of 12.7 million shares of our common stock pursuant to a shelf registration statement previously filed with the SEC, which the SEC declared effective on May 8, 2009. We received approximately $65 million in net proceeds from the offering after deducting the underwriting discount and related offering expenses.

Restructurings (Narrative) (Details) $ in Thousands	3 Months Ended		12 Months Ended	27 Months Ended
Restructurings (Narrative) (Details) $ in Thousands	Mar. 31, 2012 USD ($) employee	Mar. 31, 2011 USD ($)	Dec. 31, 2010 employee	Mar. 31, 2012 USD ($) employee
Restructuring Cost and Reserve [Line Items]
Overall reduction of employees \| employee			386
Aggregate reduction in headcount \| employee	402			402
Aggregate restructuring charges	$ (195)	$ 4,767
Termination Benefits [Member]
Restructuring Cost and Reserve [Line Items]
Aggregate restructuring charges				$ 20,200
Facility-Charges And Impairment Of Various Assets [Member]
Restructuring Cost and Reserve [Line Items]
Aggregate restructuring charges				22,500
2010 And 2011 Restructuring Plans [Member]
Restructuring Cost and Reserve [Line Items]
Aggregate restructuring charges				$ 42,700
South San Francisco Facilities [Member]
Restructuring Cost and Reserve [Line Items]
Expected additional payment for restructuring	$ 1,700

Stock-Based Compensation (Summary Of All RSU Activity) (Details)	3 Months Ended
	Mar. 31, 2012 USD ($) $ / shares shares
Stock-Based Compensation [Abstract]
RSUs outstanding at December 31, 2011, Shares \| shares	1,391,691
Awarded, Shares \| shares	18,734
Released, Shares \| shares	(288,161)
Forfeited, Shares \| shares	(18,387)
RSUs outstanding at March 31, 2012, Shares \| shares	1,103,877
RSUs outstanding at December 31, 2011, Weighted Average Grant Date Fair Value \| $ / shares	$ 6.92
Awarded, Weighted Average Grant Date Fair Value \| $ / shares	5.27
Released, Weighted Average Grant Date Fair Value \| $ / shares	7.31
Forfeited, Weighted Average Grant Date Fair Value \| $ / shares	7.45
RSUs outstanding at March 31, 2012, Weighted Average Grant Date Fair Value \| $ / shares	$ 6.79
ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsOutstandingWeightedAverageRemainingContractualTerm	1.37
RSUs outstanding at March 31, 2012, Aggregate Intrinsic Value \| $	$ 5,718,083,000

Condensed Consolidated Statements Of Cash Flows - USD ($)
$ in Thousands

3 Months Ended

Mar. 31, 2012

Mar. 31, 2011

Cash flows from operating activities:

Net loss

$ (26,151)

$ (27,490)

Adjustments to reconcile net loss to net cash used in operating activities:

Depreciation and amortization

1,233

1,929

Stock-based compensation expense

2,332

3,603

Restructuring (credit) charge for property and equipment

(195)

122

Accretion of debt discount

2,193

1,878

Other

1,304

478

Changes in assets and liabilities:

Other receivables

27,870

125

Prepaid expenses and other current assets

(268)

(1,279)

Other assets

(116)

114

Accounts payable and other accrued expenses

(2,736)

4,351

Restructuring liability

(1,865)

(1,478)

Other long-term liabilities

(87)

(232)

Deferred revenue

(18,480)

(25,397)

Net cash used in operating activities

(14,966)

(43,276)

Cash flows from investing activities:

Purchases of property and equipment

(72)

(405)

Proceeds from sales of property and equipment

847

Decrease in restricted cash and investments

2,200

Proceeds from maturities of marketable securities

60,315

26,718

Purchases of marketable securities

(113,368)

(60,015)

Net cash used in investing activities

(52,278)

(31,502)

Cash flows from financing activities:

Proceeds from issuance of common stock, net of offering costs

64,990

179,347

Proceeds from exercise of stock options and warrants, net of repurchases

109

3,794

Principal payments on notes payable and bank obligations

(1,646)

(3,752)

Net cash provided by financing activities

63,453

179,389

Net (decrease) increase in cash and cash equivalents

(3,791)

104,611

Cash and cash equivalents, at beginning of period

74,257

^[1]

97,440

Cash and cash equivalents, at end of period

$ 70,466

$ 202,051

[1]	The condensed consolidated balance sheet at December 31, 2011 has been derived from the audited consolidated financial statements at that date but does not include all of the information and footnotes required by U.S. generally accepted accounting principles for complete financial statements.

Income Taxes (Details) $ in Thousands	3 Months Ended
Income Taxes (Details) $ in Thousands	Mar. 31, 2012 USD ($)
Income Taxes [Abstract]
Provision for income tax	$ 11

Restructurings

3 Months Ended

Mar. 31, 2012

Restructurings [Abstract]

Restructurings

NOTE 4: Restructurings

During 2010, we implemented two restructurings that resulted in an overall reduction in our workforce of 386 employees. In March 2011, we implemented an additional restructuring that resulted in further reductions in 2011. Taking into consideration employees who have since been recalled, there has been an aggregate reduction in headcount from the 2010 and 2011 restructurings of 402 employees. The restructurings are a consequence of our decision to focus our proprietary resources and development efforts on the late-stage development and commercialization of cabozantinib.

Since the inception of the 2010 and 2011 restructurings, we have recorded aggregate restructuring charges of $42.7 million, of which $20.2 million related to termination benefits and $22.5 million related to facility charges and the impairment of various assets. We had a restructuring credit of $0.2 million for the three months ended March 31, 2012. The credit was primarily due to asset auctions and direct sales of previously impaired assets, partially offset by facility-related charges due to the exit of all or portions of three of our South San Francisco buildings. The total outstanding restructuring liability is included in Current portion of restructuring and Long-term portion of restructuring on our Condensed Consolidated Balance Sheet and is based upon restructuring charges recognized as of March 31, 2012 in connection with the 2010 and 2011 restructurings. As of March 31, 2012, the components of these liabilities are summarized in the following table (in thousands):


	Employee Severance And Other Benefits			Facility Charges			Asset Impairment			Legal and Other Fees		Total
Ending accrual balance as of December 31, 2011	$	6		$	13,921		$	—		$	51	$	13,978
Restructuring (credit) charge		(5	)		248			(438	)		—		(195	)
Cash payments		(1	)		(1,864	)		—			—		(1,865	)
Adjustments or non-cash credits		—			—			(409	)		—		(409	)
Proceeds from sale of assets		—			—			847			—		847

Ending accrual balance as of March 31, 2012	$	—		$	12,305		$	—		$	51	$	12,356

With respect to our restructurings, we expect to incur additional restructuring charges of $1.7 million relating to the previously mentioned exit and sublease of our South San Francisco facilities. These charges will be recorded through the end of 2017, or the end of the building lease terms.

The remaining 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.

- Definition

The entire disclosure for restructuring and related activities. Description of restructuring activities such as exit and disposal activities, include facts and circumstances leading to the plan, the expected plan completion date, the major types of costs associated with the plan activities, total expected costs, the accrual balance at the end of the period, and the periods over which the remaining accrual will be settled.

+ References + Details

Restructurings (Summary Of Components Of Restructuring Liability) (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2012 USD ($)
Restructuring Cost and Reserve [Line Items]
Ending accrual balance as of December 31, 2011	$ 13,978
Restructuring (credit) charge	(195)
Cash payments	(1,865)
Adjustments or non-cash credits	(409)
Proceeds from sale of assets	847
Ending accrual balance as of March 31, 2012	12,356
Employee Severance And Other Benefits [Member]
Restructuring Cost and Reserve [Line Items]
Ending accrual balance as of December 31, 2011	6
Restructuring (credit) charge	(5)
Cash payments	(1)
Facility Charges [Member]
Restructuring Cost and Reserve [Line Items]
Ending accrual balance as of December 31, 2011	13,921
Restructuring (credit) charge	248
Cash payments	(1,864)
Ending accrual balance as of March 31, 2012	12,305
Asset Impairment [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring (credit) charge	(438)
Adjustments or non-cash credits	(409)
Proceeds from sale of assets	847
Legal And Other Fees [Member]
Restructuring Cost and Reserve [Line Items]
Ending accrual balance as of December 31, 2011	51
Restructuring (credit) charge
Cash payments
Adjustments or non-cash credits
Proceeds from sale of assets
Ending accrual balance as of March 31, 2012	$ 51

Income Taxes	3 Months Ended
Income Taxes	Mar. 31, 2012
Income Taxes [Abstract]
Income Taxes	NOTE 6: Income Taxes We recorded an income tax provision of $0.01 million for the three months ended March 31, 2012 for tax-related interest associated with the audit by the Internal Revenue Service of our 2008, 2009 and 2010 tax years.

- Definition

The entire disclosure for income taxes. Disclosures may include net deferred tax liability or asset recognized in an enterprise's statement of financial position, net change during the year in the total valuation allowance, approximate tax effect of each type of temporary difference and carryforward that gives rise to a significant portion of deferred tax liabilities and deferred tax assets, utilization of a tax carryback, and tax uncertainties information.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 08
-Paragraph h
-Article 4

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 109
-Paragraph 136, 172
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 109
-Paragraph 43, 44, 45, 46, 47, 48, 49
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 15
-URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32718-109319

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 9
-URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32639-109319

Reference 6: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(h))
-URI http://asc.fasb.org/extlink&oid=6881521&loc=d3e23780-122690

Reference 7: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32537-109319

Reference 8: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32559-109319

+ Details