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Stock-Based Compensation Valuation Assumptions (Details) (Options and SSARs [Member], USD $)
12 Months Ended
Dec. 31, 2011
years
Dec. 31, 2010
years
Dec. 31, 2009
years
Options and SSARs [Member]
     
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Expected stock price volatility 64.00% 59.00% 50.00%
Expected dividend yield 0.00% 0.00% 0.00%
Risk-free interest rate 2.10% 2.40% 1.80%
Expected life of options 5.2 5.1 5.0
Weighted average fair value of options and SSARs granted $ 5.59 $ 3.73 $ 1.00