Earnings Per Share - Basic and Diluted (Details)	12 Months Ended
Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Basic:
Weighted average shares outstanding	27,138,927	26,990,059	26,899,373
Effect of dilutive securities:
Common stock options	0	0	266,479
Total weighted average shares outstanding assuming dilution	27,138,927	26,990,059	27,165,852
Shares of common stock issued from the exercise of stock options	56,658	32,124	82,510

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

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The average number of shares or units issued and outstanding that are used in calculating diluted EPS or earnings per unit (EPU), determined based on the timing of issuance of shares or units in the period.

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- Definition

Number of [basic] shares or units, after adjustment for contingently issuable shares or units and other shares or units not deemed outstanding, determined by relating the portion of time within a reporting period that common shares or units have been outstanding to the total time in that period.

+ References

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Reference 5: http://www.xbrl.org/2003/role/presentationRef

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-Name Emerging Issues Task Force (EITF)

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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.

Reference 6: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

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Reference 7: http://www.xbrl.org/2003/role/presentationRef

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+ Details