Earnings Per Share - Summary of Earnings Per Share, Basic and Diluted (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019		Dec. 31, 2018	Dec. 31, 2017
Earnings Per Share [Abstract]
Net income	$ 235,510	$ 225,805	$ 261,651	$ 172,107	$ 302,000	$ 157,694	$ 176,852	$ 174,937	$ 895,073	[1],[2]	$ 811,483	$ 740,200	[3],[4]
Denominator for basic earnings per share (in shares)	86,600	86,662	86,360	85,941	87,636	88,456	89,169	89,765	86,401	[2]	88,750	91,129	[4]
Dilutive securities (in shares)									3,669		3,401	2,465
Denominator for diluted earnings per share (in shares)	90,427	90,522	90,131	89,244	90,703	92,081	92,702	93,250	90,070	[2]	92,151	93,594	[4]
Basic earnings per share (in usd per share)	$ 2.72	$ 2.61	$ 3.03	$ 2.00	$ 3.45	$ 1.78	$ 1.98	$ 1.95	$ 10.36	[2]	$ 9.14	$ 8.12	[4]
Diluted earnings per share (in usd per share)	$ 2.60	$ 2.49	$ 2.90	$ 1.93	$ 3.33	$ 1.71	$ 1.91	$ 1.88	$ 9.94	[2]	$ 8.81	$ 7.91	[4]

[1] Reflects the impact of the Company's adoption of ASU 2016-02 "Leases", on January 1, 2019 using the modified retrospective transition method. The adoption of the Leases guidance resulted in an adjustment to other assets, other current liabilities and other noncurrent liabilities in our consolidated balance sheet for the cumulative effect of applying the standard. Financial results reported in periods prior to 2019 are unchanged.

[2] Reflects the impact of the Company's adoption of ASU 2016-02 "Leases", on January 1, 2019, using a modified retrospective transition method. Under this method, financial results reported in periods prior to 2019 are unchanged. Refer to footnote 14.

[3] Reflects the impact of the Company's adoption of Accounting Standards Update 2016-18, Statement of Cash Flows (Topic 230), which was adopted by the Company on January 1, 2018 and applied retrospectively to results for 2017. The adoption of Topic 230 resulted in the statement of cash flows presenting the changes in the total of cash, cash equivalents and restricted cash. As a result, the Company will no longer present transfers between cash and cash equivalents and restricted cash in the statement of cash flows.

[4] The Company applied the modified retrospective transition method when adopting ASC 606, therefore the Company's 2017 prior period results were not restated to reflect ASC 606.