Earnings Per Share and Capital Structure Stock-based Awards (Details)	12 Months Ended
Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Stock-based awards excluded from diluted EPS calculation (antidilutive)	1,100,000	1,300,000	456,000

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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Reference 2: http://www.xbrl.org/2003/role/presentationRef

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-Name Accounting Standards Codification

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-Name Accounting Standards Codification

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-Name Accounting Standards Codification

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-Name Accounting Standards Codification

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+ Details