Earnings Per Share (Details 1) (USD $)	6 Months Ended
Jun. 30, 2012	Jun. 30, 2011
Stock appreciation rights were outstanding, but not included in the diluted loss per share calculation
Number of shares	1,072,808	464,314
Price ranges per share		$ 46.78
Price ranges per share, minimum	$ 34.06
Price ranges 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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Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

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-Publisher FASB

-Name Accounting Standards Codification

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-Name Accounting Standards Codification

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+ Details