Treasury Stock - Additional Information (Detail) (USD $)	0 Months Ended	3 Months Ended
	Feb. 28, 2014	Mar. 31, 2014	Mar. 31, 2013
Equity, Class of Treasury Stock [Line Items]
Stock Repurchase Program, Authorized Amount	$ 300,000,000.0
Repurchase of common stock		$ 113,000	$ 250,991,000
Treasury shares issued		250,394
Issuance of treasury shares, average cost per share		$ 6.35
Shares repurchased to satisfy employee withholding tax requirements resulting from certain restricted stock units becoming vested		109,293
Common stock repurchased, average cost (in dollars per share)		$ 48.19
Treasury stock, shares		24,002,203