Goodwill, Mortgage Servicing Rights, and Other Intangible Assets - Key Economic Assumptions (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Goodwill and Intangible Assets Disclosure [Abstract]
Weighted-average prepayment speed assumption (constant prepayment rate)	6.29%	6.12%
Impact on fair value of 10% adverse change	$ (206)	$ (183)
Impact on fair value of 20% adverse change	$ (401)	$ (356)
Weighted-average option adjusted spread	6.10%	5.77%
Impact on fair value of 100 basis points adverse change	$ (369)	$ (341)
Impact on fair value of 200 basis points adverse change	$ (709)	$ (655)