Goodwill and Other Intangible Assets - Schedule of Other Intangible Assets by Asset Class (Details) - USD ($) $ in Millions	Sep. 30, 2025	Sep. 03, 2025	Dec. 31, 2024
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 8,742		$ 9,172
Accumulated Amortization and Impairment	2,915		2,429
Total	5,827		6,743
Held-for-sale | NFP Acquisition
Finite-Lived Intangible Assets [Line Items]
Gross intangibles held for sale		$ 754
Customer-related and contract-based
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	7,660		7,994
Accumulated Amortization and Impairment	2,488		2,050
Total	5,172		5,944
Tradenames
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	715		812
Accumulated Amortization and Impairment	103		66
Total	612		746
Technology and other
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	367		366
Accumulated Amortization and Impairment	324		313
Total	$ 43		$ 53