Stock-Based Compensation - Stock Options Activity (Details) (USD $)	6 Months Ended
Jun. 30, 2012
Stock Options [Roll Forward]
Outstanding December 31, 2011 (shares)	5,679,579
Granted (shares)	1,133,091
Exercised (shares)	0
Canceled (shares)	(311,081)
Forfeited (shares)	(133,639)
Outstanding June 30, 2012 (shares)	6,367,950
Exercisable as of June 30, 2012 (shares)	3,942,735
Weighted Average Exercise Price [Roll Forward]
Oustanding December 31, 2011 (dollars per share)	$ 19.87
Granted (dollars per share)	$ 5.82
Exercised (dollars per share)	$ 0.00
Canceled (dollars per share)	$ 27.69
Forfeited (dollars per share)	$ 10.50
Outstanding June 30, 2012 (dollars per share)	$ 17.13
Exercisable as of June 30, 2012 (dollars per share)	$ 22.84

Share-based Compensation Arrangement by Share-based Payment Award, Options, Cancellations in Period

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Options, Cancellations in Period, Weighted Average Exercise Price

+ References

No definition available.

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- Definition

The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

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- Definition

The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

+ References

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- Definition

The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan.

+ References

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

-Publisher FASB

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-Subparagraph b(1)(f)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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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- Definition

Gross number of share options (or share units) granted during the period.

+ References

No definition available.

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- Definition

The number of shares reserved for issuance under stock option agreements awarded under the plan that validly exist and are outstanding as of the balance sheet date, including vested options.

+ References

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

-Publisher FASB

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-Number 123R

-Paragraph A240

-Subparagraph b(1)(b)

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-Publisher FASB

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- Definition

Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

+ References

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- Definition

Weighted average price at which option holders acquired shares when converting their stock options into shares.

+ References

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- Definition

Weighted average price at which grantees could have acquired the underlying shares with respect to stock options that were terminated.

+ References

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- Definition

Weighted average price at which grantees can acquire the shares reserved for issuance on stock options awarded.

+ References

No definition available.

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Number of share options (or share units) exercised during the current period.

+ References

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-Name Accounting Standards Codification

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