Stock-Based Compensation (Details 1) (USD $)	6 Months Ended
Jun. 30, 2012
Share-based option activity, adjusted for the stock split, including options
Shares Outstanding at December 31, 2011	8,744,649
Shares Granted	397,951
Shares cancelled	(617,678)
Shares Outstanding at June 30, 2012	8,524,922
Shares Vested and expected to vest at June 30, 2012	7,210,354
Shares Exercisable at June 30, 2012	4,531,956
Weighted average exercise price outstanding at December 31, 2011	$ 38.15
Weighted average exercise price granted	$ 15.11
Weighted average exercise price cancelled	$ 26.25
Weighted average exercise price outstanding at June 30, 2012	$ 32.85
Weighted average exercise price vested and expected to vest at June 30, 2012	$ 32.04
Weighted average exercise price exercisable at June 30, 2012	$ 28.15

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.

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-Name Accounting Standards Codification

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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.

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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.

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

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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.

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

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As of the balance sheet date, the number of shares into which fully vested and expected to vest stock options outstanding can be converted under the option plan.

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