Stockholders' Equity - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands		3 Months Ended
	Apr. 26, 2017	Mar. 31, 2017	Mar. 31, 2016	Dec. 31, 2016
Schedule Of Stockholders Equity [Line Items]
Shares repurchased, value		$ 106,048	$ 83,140
Share repurchase remaining authorization		$ 249,078
Preferred stock, shares authorized		15,000,000		15,000,000
Preferred stock, par value		$ 0.01		$ 0.01
Dividend declared per share of common stock		$ 1.58	$ 1.55
Subsequent Event [Member]
Schedule Of Stockholders Equity [Line Items]
Dividend declared per share of common stock	$ 0.41
Dividend payable date	May 19, 2017
Dividend date of record	May 08, 2017
Dividend declare date	Apr. 26, 2017
January and April, 2016 [Member]
Schedule Of Stockholders Equity [Line Items]
Share repurchase remaining authorization		$ 13,078
Share repurchase authorization expiration date		Dec. 31, 2017
November, 2016 [Member]
Schedule Of Stockholders Equity [Line Items]
Share repurchase remaining authorization		$ 236,000
Share repurchase authorization expiration date		Dec. 31, 2018
Series A Preferred Stock [Member]
Schedule Of Stockholders Equity [Line Items]
Preferred stock, shares outstanding		0		0
Series B Preferred Stock [Member]
Schedule Of Stockholders Equity [Line Items]
Preferred stock, shares outstanding		0		0
Executive Officers [Member] | Class A Common Stock [Member]
Schedule Of Stockholders Equity [Line Items]
Shares repurchased, value		$ 14,700	$ 3,100