Stock-Based Compensation (Details 1) (USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended
Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Summary of stock option activity
Options outstanding, Stock Options, Beginning balance	236	291	324
Granted, Stock Options
Exercised, Stock Options	236	55	33
Forfeited, Stock Options
Options outstanding, Stock Options, Ending balance	0	236	291
Options outstanding, Weighted Average Exercise Price, Beginning balance	$ 9.82	$ 9.29	$ 9.01
Granted, Weighted Average Exercise Price
Exercised, Weighted Average Exercise Price	$ 9.82	$ 6.99	$ 6.65
Forfeited, Weighted Average Exercise Price
Options outstanding, Weighted Average Exercise Price, Ending balance	$ 0.00	$ 9.82	$ 9.29

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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-Name Statement of Financial Accounting Standard (FAS)

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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 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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