Earnings Per Share (Details)	3 Months Ended	6 Months Ended
Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
Earnings Per Share [Abstract]
Weighted average common shares outstanding for basic calculation	134,854,024	141,398,901	134,816,074	142,716,771
Add: Effect of stock options and restricted stock	201,809	655,045	171,517	665,654
Weighted average common shares outstanding for diluted calculation	135,055,833	142,053,946	134,987,591	143,382,425
Shares which exclude consideration of stock options in calculation of diluted shares outstanding	1,591,000	884,000	1,590,814	871,000

Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

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+ Details

- Definition

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.

+ References+ 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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+ Details