Capital Stock - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands		12 Months Ended
	Nov. 15, 2016	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Jun. 11, 2018	Jun. 10, 2018	Oct. 17, 2016
Stockholders Equity Note [Line Items]
Common stock, shares authorized		400,000,000	200,000,000		400,000,000	200,000,000
Common and Preferred Stock, Shares Authorized		410,000,000	210,000,000		410,000,000	210,000,000
Common Stock, par value		$ 0.01	$ 0.01		$ 0.01	$ 0.01
Preferred stock, shares authorized		10,000,000	10,000,000		10,000,000	10,000,000
Preferred stock, par value		$ 0.01	$ 0.01		$ 0.01	$ 0.01
Stock Repurchase Program, Additional Repurchase Authorization							$ 300,000
Common stock repurchased, total purchase price		$ 7,828	$ 4,123	$ 280,736
Common stock purchased through modified dutch auction tender offer - in shares	10,617,810
Common stock purchased through modified dutch auction tender offer - price per share	$ 25.38
Common stock purchased through modified dutch auction tender offer - total purchase price in dollars	$ 269,400
Fees And Expenses Incurred Related To Modified Dutch Auction Tender Offer	$ 700
Treasury Stock, Value, Acquired, Cost Method		4,771		$ 277,306
Common stock repurchase, remaining authorized amount		$ 124,600
Treasury stock, shares		64,682,900	64,727,152
Activity related to restricted stock units vested [Member]
Stockholders Equity Note [Line Items]
Treasury shares issued		339,972	421,108	363,368
Average cost for restricted stock units		$ 3.12	$ 3.15	$ 3.15
Shares repurchased to satisfy employee withholding tax requirements resulting from certain restricted stock units becoming vested		107,420	138,080	134,122
Common stock repurchased, average cost		$ 28.46	$ 30.24	$ 25.58
Non-tender offer repurchase [Member]
Stockholders Equity Note [Line Items]
Repurchases of common stock		188,300		294,930
Common stock repurchased, total purchase price		$ 4,800		$ 7,200
Treasury Stock Acquired, Average Cost Per Share		$ 25.31		$ 24.40
Board of Director Members, Executive Officers, Related Family Foundations
Stockholders Equity Note [Line Items]
Repurchases of common stock	3,358,572
Treasury Stock Acquired, Average Cost Per Share	$ 25.38
Treasury Stock, Value, Acquired, Cost Method	$ 85,200