Share Based Compensation (Details 3) (USD $)	6 Months Ended
Jun. 30, 2012
Share-Based Compensation [Abstract]
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
Options outstanding at June 30, 2012, Options Exercisable	293,905
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 June 30, 2012, Shares	387,758
Options outstanding at June 30, 2012, Weighted Average Exercise Price	$ 21.95

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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.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph A240

-Subparagraph b(1)(c), d(2)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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- Definition

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.

+ References

+ Details

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- Definition

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

+ References

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- Definition

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.

+ References

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-Publisher FASB

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- Definition

Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

+ References

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

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- Definition

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

+ References

No definition available.

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

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