Goodwill and Other Intangible Assets - Schedule of Intangible Assets by Type (Details) - USD ($)	3 Months Ended	9 Months Ended
	Sep. 30, 2020	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019
Finite-Lived Intangible Assets, Net [Abstract]
Finite-lived intangible assets, gross	$ 4,918,000,000	$ 4,918,000,000		$ 5,994,000,000
Finite-lived intangible assets, accumulated amortization	(2,734,000,000)	(2,734,000,000)		(2,855,000,000)
Finite-lived intangible assets, net	2,184,000,000	2,184,000,000		3,139,000,000
Indefinite-lived intangible assets	2,193,000,000	2,193,000,000		2,242,000,000
Intangible assets, gross	7,111,000,000	7,111,000,000		8,236,000,000
Other intangible assets, net	4,377,000,000	4,377,000,000		5,381,000,000
Intangible assets impairment	4,000,000	729,000,000	$ 0
Customer relationships
Finite-Lived Intangible Assets, Net [Abstract]
Finite-lived intangible assets, gross	2,243,000,000	2,243,000,000		3,027,000,000
Finite-lived intangible assets, accumulated amortization	(888,000,000)	(888,000,000)		(1,045,000,000)
Finite-lived intangible assets, net	1,355,000,000	1,355,000,000		1,982,000,000
Intangible assets impairment		480,000,000
Technology
Finite-Lived Intangible Assets, Net [Abstract]
Finite-lived intangible assets, gross	1,097,000,000	1,097,000,000		1,075,000,000
Finite-lived intangible assets, accumulated amortization	(663,000,000)	(663,000,000)		(626,000,000)
Finite-lived intangible assets, net	434,000,000	434,000,000		449,000,000
Intangible assets impairment		8,000,000
Trade names and trademarks
Finite-Lived Intangible Assets, Net [Abstract]
Finite-lived intangible assets, gross	325,000,000	325,000,000		696,000,000
Finite-lived intangible assets, accumulated amortization	(178,000,000)	(178,000,000)		(254,000,000)
Finite-lived intangible assets, net	147,000,000	147,000,000		442,000,000
Intangible assets impairment		236,000,000
Capitalized software
Finite-Lived Intangible Assets, Net [Abstract]
Finite-lived intangible assets, gross	1,253,000,000	1,253,000,000		1,193,000,000
Finite-lived intangible assets, accumulated amortization	(1,005,000,000)	(1,005,000,000)		(928,000,000)
Finite-lived intangible assets, net	248,000,000	248,000,000		265,000,000
Intangible assets impairment		3,000,000
Other
Finite-Lived Intangible Assets, Net [Abstract]
Finite-lived intangible assets, gross	0	0		3,000,000
Finite-lived intangible assets, accumulated amortization	0	0		(2,000,000)
Finite-lived intangible assets, net	$ 0	$ 0		$ 1,000,000