Acquisitions, Goodwill, and Acquired Intangible Assets - Summary of Goodwill Activity by Segment (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Goodwill [Roll Forward]
Goodwill, balance at beginning of period	$ 14,548	$ 13,350
New acquisitions	189	1,228
Other adjustments	17	(30)
Goodwill, balance at end of period	14,754	14,548
North America
Goodwill [Roll Forward]
Goodwill, balance at beginning of period	12,191	11,165
New acquisitions	71	1,031
Other adjustments	2	(5)
Goodwill, balance at end of period	12,264	12,191
International
Goodwill [Roll Forward]
Goodwill, balance at beginning of period	1,270	1,108
New acquisitions	29	177
Other adjustments	1	(15)
Goodwill, balance at end of period	1,300	1,270
AWS
Goodwill [Roll Forward]
Goodwill, balance at beginning of period	1,087	1,077
New acquisitions	89	20
Other adjustments	14	(10)
Goodwill, balance at end of period	$ 1,190	$ 1,087