Capital Stock - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands		12 Months Ended
	Feb. 08, 2013	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Mar. 17, 2015	Feb. 28, 2014
Stockholders Equity Note [Line Items]
Common stock, shares authorized		200,000,000	200,000,000
Common Stock, par value		$ 0.01	$ 0.01
Preferred stock, shares authorized		10,000,000
Preferred stock, par value		$ 0.01
Common stock authorized for repurchase						$ 300,000
Common stock repurchased, total purchase price		$ 170,132	$ 24,666	$ 267,607
Common stock purchased through modified dutch auction tender offer - in shares	5,524,861				2,766,354
Common stock purchased through modified dutch auction tender offer - price per share	$ 45.25				$ 58.50
Common stock purchased through modified dutch auction tender offer - total purchase price in dollars	$ 250,000				$ 161,800
Fees And Expenses Incurred Related To Modified Dutch Auction Tender Offer	$ 1,000				$ 700
Treasury Stock, Value, Acquired, Cost Method		170,132	$ 24,666	$ 267,607
Common stock repurchase, remaining authorized amount		$ 106,000
Treasury stock, shares		27,163,343	24,352,887
Activity related to restricted stock units vested [Member]
Stockholders Equity Note [Line Items]
Treasury shares issued		146,160	531,024	149,304
Average cost for restricted stock units		$ 6.30	$ 6.30	$ 6.63
Shares repurchased to satisfy employee withholding tax requirements resulting from certain restricted stock units becoming vested		50,841	234,440	58,812
Common stock repurchased, average cost		$ 56.88	$ 48.87	$ 43.55
Non-tender offer repurchase [Member]
Stockholders Equity Note [Line Items]
Repurchases of common stock		139,421	508,667	354,154
Common stock repurchased, total purchase price		$ 7,600	$ 24,700	$ 16,600
Treasury Stock Acquired, Average Cost Per Share		$ 54.71	$ 48.47	$ 46.90
Stock Repurchase Program [Member] | Board of Directors Co-Chairman [Member]
Stockholders Equity Note [Line Items]
Repurchases of common stock	515,806
Treasury Stock Acquired, Average Cost Per Share	$ 45.25
Treasury Stock, Value, Acquired, Cost Method	$ 23,300