Treasury Stock - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands	9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Feb. 28, 2014
Equity, Class of Treasury Stock [Line Items]
Remaining authorized repurchase amount	$ 98,800
Payments for Repurchase of Common Stock	$ 7,200	$ 170,132
Treasury stock (shares)	27,216,596
Stock Repurchase Program [Member]
Equity, Class of Treasury Stock [Line Items]
Authorized repurchase amount			$ 300,000
Treasury Stock, Shares, Acquired	147,465
Remaining authorized repurchase amount	$ 98,800
Average cost per share of treasury stock acquired	$ 48.81
Payments for Repurchase of Common Stock	$ 7,200
2004 Amended and Restated Stock Incentive Plan
Equity, Class of Treasury Stock [Line Items]
Treasury shares issued (shares)	141,684
Issuance of treasury shares, average cost per share (usd per share)	$ 6.30
Shares repurchased to satisfy minumum employee withholding tax requirements resulting from the vesting of such restricted stock units (shares)	47,472
Average cost per share of treasury stock acquired	$ 51.27