Loan Servicing - Analysis of Activity in Residential MSRs (Details) - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021
Servicing Asset at Fair Value, Amount [Roll Forward]
MSRs, carrying value, beginning balance	$ 2,633
MSRs, carrying value, ending balance	3,466
Residential MSRs
Servicing Asset at Fair Value, Amount [Roll Forward]
MSRs, carrying value, beginning balance	2,305	$ 1,778
Additions	257	347
Realization of expected net servicing cash flows, passage of time and other	(215)	(387)
MSRs, carrying value, ending balance	3,148	1,963
Change in fair value due to changes in valuation inputs or assumptions:
Prepayment speeds	630	20
OAS	(24)	153
Residential MSRs | Servicing rights acquisition
Servicing Asset at Fair Value, Amount [Roll Forward]
Additions	$ 195	$ 52