Stock-Based Compensation (Details 2) (Stock options [Member], USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended
Dec. 31, 2011 years
Stock options [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of Share outstanding, Beginning balance	16,899
Number of Share, Options granted	2,808
Number of Share, Options exercised	(785)
Number of Share, Options forfeited & canceled	(1,876)
Number of Share outstanding, Ending balance	17,046
Weighted Average Exercise Price, Outstanding, Beginning balance	$ 9.40
Weighted Average Exercise Price, Options granted	$ 9.68
Weighted Average Exercise Price, Options exercised	$ 4.99
Weighted Average Exercise Price, Options forfeited & Canceled	$ 12.66
Weighted Average Exercise Price, Outstanding, Ending balance	$ 9.29
Weighted Average Remaining Contractual Life, ending balance	5.06
Aggregate Intrinsic Value, Outstanding, Ending balance	$ 2,924
Vested & Expected to Vest, Outstanding Number of Shares	16,717
Vested & expected to vest, Weighted-Average Exercise Price per share	$ 9.27
Vested & expected to Vest, Weighted-Average Remaining Contractual Life	5.03
Vested & expected to Vest, Aggregate Intrinsic Value	2,894
Exercisable, Number of Shares	11,174
Exercisable, Weighted Average Exercise Price per share	$ 9.08
Exercisable, Weighted Average Remaining Contractual Life	4.38
Exercisable, Aggregate Intrinsic Value	$ 2,051

Share Based Compensation Arrangement By Share Based Payment Award Stock Options Exercisable Intrinsic Value

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Share Based Compensation Arrangement By Share Based Payment Award Stock Options Exercisable Weighted Average Remaining Contractual Term.

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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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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 weighted average price at which option holders acquired shares when converting their stock options into shares under the plan during the reporting period.

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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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The weighted average price at which grantees could have acquired the underlying shares with respect to stock options that were terminated during the reporting period due to noncompliance with plan terms during the reporting period.

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

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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 stock options awarded under the plan during the reporting period.

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The total dollar difference between fair values of the underlying shares reserved for issuance and exercise prices pertaining to options outstanding under the plan as of the balance sheet date.

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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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The weighted average price as of the beginning of the year at which grantees can acquire the shares reserved for issuance under the stock option plan.

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The weighted average period between the balance sheet date and expiration for all awards outstanding under the plan, which may be expressed in a decimal value for number of years.

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As of the balance sheet date, the total dollar difference between fair values of the underlying shares reserved for issuance and exercise prices of fully vested and expected to vest options outstanding.

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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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As of the balance sheet date, the weighted-average exercise price for outstanding stock options that are fully vested or expected to vest.

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The weighted-average period between the balance sheet date and expiration date for fully vested and expected to vest options outstanding, which may be expressed in a decimal value for number of years.

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

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