Goodwill and Other Intangible Assets - Summary of Changes in Goodwill by Reportable Business Segment (Details) $ in Thousands	6 Months Ended
	Jun. 30, 2018 USD ($)
Goodwill [Roll Forward]
Goodwill, beginning balance	$ 4,715,823
Acquisition Accounting Adjustments	4,013
Foreign Currency	(163,630)
Goodwill, ending balance	4,556,206	[1]
North America
Goodwill [Roll Forward]
Goodwill, beginning balance	3,084,123
Acquisition Accounting Adjustments	3,993
Foreign Currency	(8,490)
Goodwill, ending balance	3,079,626
International
Goodwill [Roll Forward]
Goodwill, beginning balance	1,631,700
Acquisition Accounting Adjustments	20
Foreign Currency	(155,140)
Goodwill, ending balance	$ 1,476,580

[1] Reflects the January 1, 2018 adoption of Accounting Standards Update 2014-09, "Revenue from Contracts with Customers (Topic 606)" and related cost capitalization guidance using the modified retrospective transition method. The adoption of Topic 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 Topic 606. See footnote 1.