Share Based Compensation (Details 3) (USD $)	9 Months Ended
Sep. 30, 2012
Summary of stock option activity
Options outstanding at January 1, 2012, Shares	584,201
Options outstanding at January 1, 2012, Weighted Average Exercise Price	$ 23.32
Options outstanding at January 1, 2012, Options Exercisable	396,688
Exercised, Shares	(4,562)
Exercised, Weighted Average Exercise Price	$ 19.57
Shares Forfeited or Expired	(191,881)
Weighted Average Exercise Price Forfeited	$ 26.18
Options outstanding at September 30, 2012, Shares	387,758
Options outstanding at September 30, 2012, Weighted Average Exercise Price	$ 21.95
Options outstanding at September 30, 2012, Options Exercisable	293,905

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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For presentations that combine terminations, 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 or that expired.

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Weighted average price of options that were either forfeited or expired.

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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 price at which option holders acquired shares when converting their stock options into shares.

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

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