Mortgage Servicing Rights and Related Liabilities - Servicing Revenue (Details) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Transfers and Servicing [Abstract]
Contractually specified servicing fees(1)	$ 547,000,000	$ 407,000,000	$ 1,061,000,000	$ 791,000,000
Other service-related income(1)	16,000,000	19,000,000	38,000,000	33,000,000
Incentive and modification income(1)	16,000,000	8,000,000	34,000,000	14,000,000
Servicing late fees(1)	31,000,000	23,000,000	61,000,000	44,000,000
MSR MTM	(155,000,000)	(139,000,000)	(344,000,000)	(34,000,000)
Loss on MSR hedging activities	(103,000,000)	(111,000,000)	(225,000,000)	(52,000,000)
Gain on MSR and excess yield sales	23,000,000	32,000,000	11,000,000	32,000,000
Reclassifications(2)	(6,000,000)	(9,000,000)	(12,000,000)	(18,000,000)
Excess spread / MSR financing MTM	0	12,000,000	(6,000,000)	6,000,000
Total mark-to-market adjustments - Servicing	(69,000,000)	(63,000,000)	(112,000,000)	(2,000,000)
MSR amortization	226,000,000	148,000,000	405,000,000	273,000,000
Excess spread accretion	(9,000,000)	(11,000,000)	(18,000,000)	(21,000,000)
Total amortization, net of accretion	217,000,000	137,000,000	387,000,000	252,000,000
Originations service related fees(3)	19,000,000	16,000,000	35,000,000	27,000,000
Corporate/Xome service related fees	20,000,000	21,000,000	42,000,000	40,000,000
Other(4)	16,000,000	18,000,000	33,000,000	36,000,000
Total revenues - Service related, net	485,000,000	402,000,000	963,000,000	663,000,000
Cash Flows Between Transferor and Transferee, Servicing Fees	$ 189,000,000	$ 176,000,000	$ 374,000,000	$ 353,000,000