Common Stock Repurchase Programs - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Jun. 30, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Aug. 31, 2018
Common Stock [Line Items]
Common stock authorized for repurchase					$ 500,000
Common stock repurchased		$ 145,280	$ 302,160	$ 70,192
Company's Common stock repurchased			250,000
Common Stock [Member]
Common Stock [Line Items]
Common stock repurchased		$ 51	$ 70	$ 10
Repurchased common stock, shares		5,066,000	7,041,000	1,038,000
Restricted Stock [Member]
Common Stock [Line Items]
Number of shares withheld to satisfy minimum statutory tax withholding obligations	54,909	96,918
Amount withheld to satisfy minimum statutory tax withholding obligations	$ 2,500	$ 2,500