Earnings Per Share (Details 1) (USD $)	9 Months Ended
Sep. 30, 2011	Sep. 30, 2010
Stock appreciation rights were outstanding but not included in diluted earnings per share calculation
Number of shares	2,275,894	520,817
Price ranges per share		$ 36.94
Price ranges per share, minimum	$ 28.24
Price range per share, maximum	$ 46.78

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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-Name Accounting Standards Codification

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+ Details