Selected Quarterly Financial Data (Unaudited) - Schedule of Selected Quarterly Financial Data (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended								6 Months Ended	12 Months Ended
	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Jun. 30, 2016	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Quarterly Financial Information Disclosure [Abstract]
Revenues, net	$ 514,953	$ 484,426	$ 417,905	$ 414,262	$ 430,601	$ 451,493	$ 404,605	$ 416,166		$ 1,831,546	$ 1,702,865	$ 1,199,390
Operating income	215,975	191,055	171,168	175,955	146,149	188,460	169,151	163,774		754,153	667,534	565,449
Net income	$ 95,424	$ 129,618	$ 116,253	$ 111,090	$ 52,830	$ 116,770	$ 98,678	$ 94,153	$ 227,343	$ 452,385	$ 362,431	$ 368,707
Earnings per share:
Basic earnings per share (in usd per share)	$ 1.03	$ 1.40	$ 1.25	$ 1.20	$ 0.57	$ 1.27	$ 1.07	$ 1.03	$ 2.46	$ 4.89	$ 3.94	$ 4.37
Diluted earnings per share (in usd per share)	$ 1.00	$ 1.36	$ 1.22	$ 1.17	$ 0.56	$ 1.24	$ 1.05	$ 1.00	$ 2.39	$ 4.75	$ 3.85	$ 4.24
Weighted average shares outstanding:
Basic weighted average shares outstanding (in shares)	92,574	92,631	92,665	92,516	92,321	92,110	91,904	91,750	92,591	92,597	92,023	84,317
Diluted weighted average shares outstanding (in shares)	95,235	95,307	95,279	95,030	94,350	94,157	94,050	93,934	95,137	95,213	94,139	86,982