Segments - Schedule of Company's Segment Results (Detail) - USD ($) $ in Thousands	3 Months Ended			6 Months Ended
	Jun. 30, 2018		Jun. 30, 2017	Jun. 30, 2018		Jun. 30, 2017
Segment Reporting Information [Line Items]
Revenues, net	$ 584,985	[1]	$ 541,237	$ 1,170,484	[1]	$ 1,061,670
Operating income	264,783	[1]	216,043	524,870	[1]	411,111
Depreciation and amortization	68,610	[1]	64,709	140,112	[1]	129,575
Capital expenditures	19,400		17,804	34,614	[2]	32,600	[2]
North America
Segment Reporting Information [Line Items]
Revenues, net	370,949		342,995	735,218		672,943
Operating income	161,376		134,926	317,326		255,898
Depreciation and amortization	38,317		33,384	76,992		66,561
Capital expenditures	11,685		12,102	20,096		21,734
International
Segment Reporting Information [Line Items]
Revenues, net	214,036		198,242	435,266		388,727
Operating income	103,407		81,117	207,544		155,213
Depreciation and amortization	30,293		31,325	63,120		63,014
Capital expenditures	$ 7,715		$ 5,702	$ 14,518		$ 10,866

[1] Reflects the impact of the Company's adoption of ASC 606 and related cost capitalization guidance, which was adopted by the Company on January 1, 2018 using the modified retrospective transition method. The adoption of ASC 606 resulted in an adjustment to retained earnings in our consolidated balance sheet for the cumulative effective of applying the standard, which included costs incurred to obtain a contract, as well as presentation changes in our statements of income, including the classification of certain amounts previously classified as merchant commissions and processing expense net with revenues. As a result of the application of the modified retrospective transition method, the Company's prior period results within its annual report on Form 10-K and quarterly reports on Form 10-Q will not be restated to reflect the impact of ASC 606. See footnote 1, "Summary of Significant Accounting Policies", in the accompanying notes to the unaudited consolidated financial statements.

[2] 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.