Earnings Per Share (Details)	3 Months Ended	6 Months Ended
Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011
Weighted-average shares:
Common shares outstanding	71,723,014	75,701,045	71,709,976	77,234,869
Restricted common shares	589,163	1,017,879	609,601	956,232
Total Weighted Average Shares	72,312,177	76,718,924	72,319,577	78,191,101
Percentage of weighted-average shares:
Common shares outstanding	99.19%	98.67%	99.16%	98.78%
Restricted common shares	0.81%	1.33%	0.84%	1.22%
Total	100.00%	100.00%	100.00%	100.00%

This element represents nonvested share-based payment awards that contain non-forfeitable rights to dividends or dividend equivalents (whether paid or unpaid). Basic and dilutive earnings per share are generally disclosed for such shares using the two-class method.

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+ Details

- 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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