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Assumptions Used to Estimate Fair Value of Award with Performance and Market Vesting Conditions (Detail) (Restricted Stock Units (RSUs), USD $)
1 Months Ended
Sep. 05, 2012
May 29, 2012
Jun. 01, 2011
Restricted Stock Units (RSUs)
     
Share based Compensation Arrangement by Share based Payment Award, Fair Value Assumptions, Method Used [Line Items]      
Fair value of the Company's common stock on grant date $ 37.45 $ 39.06 $ 28.11
Expected volatility 31.73% 44.87% 47.95%
Risk-free interest rate 0.37% 0.52% 1.42%
Dividend yield 0.00% 0.00% 0.00%