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Stock-Based Compensation - Pre-Tax Compensation Expense (Income) and Related Income Tax Benefit for Stock-Based Incentives (Parenthetical) (Detail) | 12 Months Ended
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Dec. 31, 2012
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract] |
Tax rate - before valuation allowance | 37.00%

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- Definition Effective Income Tax Benefit Rate + References No definition available. + Details
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- Details
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