Earnings Per Share (Details)	3 Months Ended
Mar. 31, 2012	Mar. 31, 2011
Earnings Per Share [Abstract]
Weighted average number of shares outstanding, basic	44,367,499	35,182,811
Dilutive effect of Equity-based Incentive Awards	1,403,729	1,265,194
Weighted average number of shares outstanding, diluted	45,771,228	36,448,005
Anti-dilutive Equity-based Incentive Awards excluded from the computation of diluted income per share	7,000	7,760

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

-Publisher FASB

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-Glossary Diluted Earnings Per Share

-URI http://asc.fasb.org/extlink&oid=6510752

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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