Mortgage Servicing Rights and Related Liabilities - Servicing Revenue (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Transfers and Servicing [Abstract]
Contractually specified servicing fees(1)	$ 371	$ 280	$ 1,076	$ 831
Other service-related income(1)	0	158	68	517
Incentive and modification income(1)	5	10	23	38
Late fees(1)	19	19	57	53
Mark-to-market adjustments(2)	124	151	877	376
Amortization, net of accretion(3)	(169)	(202)	(570)	(567)
Other(4)	(18)	(65)	(88)	(224)
Total revenues - Servicing	332	351	1,443	1,024
Cumulative incurred losses related to advances and other receivables associated with inactive and liquidated loans	10	8	22	28
Servicing fee income accretion expense	14	59	74	205
Cash Flows Between Transferor and Transferee, Servicing Fees	$ 172	$ 128	$ 488	$ 353