Goodwill and Other Intangible Assets - Narrative (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019
Goodwill and Intangible Assets Disclosure [Abstract]
Gross goodwill	$ 3,119		$ 3,128
Accumulated goodwill impairment losses	536		$ 536
Amortization of intangible assets	$ 62	$ 58