Goodwill and Other Intangible Assets - Summary of Changes in Goodwill by Reportable Business Segment (Details) $ in Thousands	9 Months Ended
	Sep. 30, 2019 USD ($)
Goodwill [Roll Forward]
Goodwill, beginning balance	$ 4,542,074
Acquisitions	235,274
Acquisition Accounting Adjustments	2,914
Foreign Currency	(72,879)
Goodwill, ending balance	4,707,383	[1]
North America
Goodwill [Roll Forward]
Goodwill, beginning balance	3,087,875
Acquisitions	215,743
Acquisition Accounting Adjustments	2,914
Foreign Currency	2,022
Goodwill, ending balance	3,308,554
International
Goodwill [Roll Forward]
Goodwill, beginning balance	1,454,199
Acquisitions	19,531
Acquisition Accounting Adjustments	0
Foreign Currency	(74,901)
Goodwill, ending balance	$ 1,398,829

[1] 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 2.