Goodwill and Other Intangible Assets - Schedule of Intangible Assets (Details) - USD ($) $ in Millions	Jun. 30, 2021	Dec. 31, 2020
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 2,770	$ 2,786
Accumulated Amortization and Impairment	2,206	2,146
Total	564	640
Estimated amortization for intangible assets
Remainder of 2021	70
2022	101
2023	90
2024	73
2025	58
2026	36
Thereafter	136
Total	564	640
Customer-related and contract-based
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	2,335	2,337
Accumulated Amortization and Impairment	1,835	1,775
Total	500	562
Estimated amortization for intangible assets
Total	500	562
Tradenames
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	14	14
Accumulated Amortization and Impairment	13	13
Total	1	1
Estimated amortization for intangible assets
Total	1	1
Technology and other
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	421	435
Accumulated Amortization and Impairment	358	358
Total	63	77
Estimated amortization for intangible assets
Total	$ 63	$ 77