Stock-Based Compensation (Details)	9 Months Ended
Sep. 30, 2011
Summary of stock options activity
Stock Options Outstanding, Beginning Balance	497,686
Granted	86,048
Forfeited	(1,801)
Expired	(5,199)
Exercised	(7,337)
Stock Options Outstanding, Ending Balance	569,397
Stock Options, Exercisable	366,962

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 Statement of Financial Accounting Standard (FAS)

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The decrease in the number of shares that could be issued attributable to the lapse of rights to exercise previously issued stock options under the terms of the option agreements under the plan during the reporting period.

+ References

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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.

+ References

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Net 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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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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

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