Goodwill and Other Intangible Assets (Details 2) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Intangible assets
Impairment of Intangible Assets (Excluding Goodwill)	$ (2)	$ 5
Carrying amount of indefinite-lived intangible assets	640	641
Carrying amount of indefinite-lived intangible assets - trade names	69	69
Gross Carrying Amount	642	608
Accumulated Amortization	(534)	(495)
Net Carrying Amount	108	113
Definite-lived intangible assets acquired during the year, amount assigned	$ 25
Definite-lived intangible assets acquired during the year, weighted-average amortization period	5 years
Aggregate amortization expense for definite-lived intangible assets	$ 31	37	$ 30
Estimated intangible amortization expense for next five years:
2021	32
2022	28
2023	24
2024	11
2025	7
Customer relationships [Member]
Intangible assets
Gross Carrying Amount	193	192
Accumulated Amortization	(155)	(146)
Net Carrying Amount	38	46
Contracts [Member]
Intangible assets
Gross Carrying Amount	223	219
Accumulated Amortization	(211)	(202)
Net Carrying Amount	12	17
Other [Member]
Intangible assets
Gross Carrying Amount	226	197
Accumulated Amortization	(168)	(147)
Net Carrying Amount	$ 58	$ 50