Goodwill, Mortgage Servicing Rights, and Other Intangible Assets - Narrative (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Goodwill and Intangible Assets Disclosure [Abstract]
Gross carrying values of other intangible assets	$ 4,200	$ 1,900
Accumulated amortization for other intangible assets	994	679
Carrying value of finite-lived intangible assets	2,000	707
Carrying value of indefinite-lived intangible assets	1,200	517
Business Acquisition [Line Items]
Amortization expense for other intangible assets	$ 315	$ 145
CIFM
Business Acquisition [Line Items]
Percentage interest acquired	51.00%