Stock-Based Compensation (Details 3) (Options, USD $) In Millions, except Per Share data, unless otherwise specified	12 Months Ended
Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Options
Stock-Based Compensation
Outstanding shares fully vested and expected to vest (in shares)	9.5
Remaining contractual life of options fully vested and expected to vest	3 years 2 months 8 days
Weighted average exercise price of options fully vested and expected to vest (in dollars per share)	$ 4.17
Aggregate intrinsic value of options fully vested and expected to vest (in dollars)	$ 3.2
Fair value of shares vested (in dollars)	2.4
Total intrinsic value of awards exercised (in dollars)	2.7	2.4	2.4
Awards exercisable (in shares)	6.4
Weighted average exercise price of awards exercisable (in dollars per share)	$ 4.41
Unamortized compensation cost, net of expected forfeitures	$ 5.0
Weighted average period for recognition of unamortized compensation cost	2 years 7 months 6 days

As of the balance sheet date, the aggregate unrecognized cost of equity-based awards made to employees under equity-based compensation awards that have yet to vest.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

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Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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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 total accumulated difference between fair values of underlying shares on dates of exercise and exercise price on options which were exercised (or share units converted) into shares during the reporting period under the plan.

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Amount of difference between fair value 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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Weighted average remaining contractual term for fully vested and expected to vest options outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Fair value of options vested. Excludes equity instruments other than options, for example, but not limited to, share units, stock appreciation rights, restricted stock.

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