Share-Based Payment Arrangements (Details) (USD $) In Thousands, except Share data, unless otherwise specified	6 Months Ended
Jun. 30, 2012
Stock Options, Outstanding at January 1, 2012	1,419,989
Stock Options, Granted	0
Stock Options, Exercised	0
Stock Options, Forfeited or expired	0
Stock Options, Outstanding at June 30, 2012	1,419,989
Stock Options, Exercisable at June 30, 2012	1,126,418
Weighted Average Exercise Price, Outstanding at January 1, 2012	$ 9.66
Weighted Average Exercise Price, Outstanding at June 30, 2012	$ 9.66
Weighted Average Exercise Price, Exercisable at June 30, 2012	$ 10.42
Average Remaining Contractual Term, Outstanding at June 30, 2012	5 years 8 months 12 days
Average Remaining Contractual Term, Exercisable at June 30, 2012	5 years 4 months 24 days
Aggregate Intrinsic Value,Outstanding at June 30, 2012	$ 679
Aggregate Intrinsic Value, Exercisable at June 30, 2012	$ 353

Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of vested portions of options outstanding and currently exercisable.

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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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Weighted average remaining contractual term for vested portions of options outstanding and currently exercisable or convertible, 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 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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Net number of share options (or share units) granted during the period.

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Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of options outstanding.

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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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Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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

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