Goodwill and Other Intangible Assets - Summary of Changes in Goodwill by Reportable Business Segment (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2019 USD ($)
Goodwill [Roll Forward]
Goodwill, beginning balance	$ 4,542,074
Acquisition Accounting Adjustments	2,711
Foreign Currency	4,314
Goodwill, ending balance	4,549,099	[1]
North America
Goodwill [Roll Forward]
Goodwill, beginning balance	3,087,875
Acquisition Accounting Adjustments	2,711
Foreign Currency	4,574
Goodwill, ending balance	3,095,160
International
Goodwill [Roll Forward]
Goodwill, beginning balance	1,454,199
Acquisition Accounting Adjustments	0
Foreign Currency	(260)
Goodwill, ending balance	$ 1,453,939

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