Mortgage Servicing Rights and Related Liabilities - Servicing Revenue (Details) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Transfers and Servicing [Abstract]
Contractually specified servicing fees(1)	$ 440,000,000	$ 371,000,000	$ 1,231,000,000	$ 1,076,000,000
Other service-related income(1)	25,000,000	22,000,000	58,000,000	94,000,000
Incentive and modification income(1)	18,000,000	4,000,000	32,000,000	22,000,000
Servicing late fees(1)	24,000,000	19,000,000	68,000,000	57,000,000
MSR MTM	(270,000,000)	(239,000,000)	(304,000,000)	(1,363,000,000)
Loss on MSR hedging activities	(192,000,000)	(100,000,000)	(244,000,000)	(329,000,000)
(Gain) loss on MSR sales	(3,000,000)	(2,000,000)	29,000,000	(1,000,000)
Reclassifications(2)	(8,000,000)	(10,000,000)	(26,000,000)	(22,000,000)
Excess spread / MSR financing MTM	(4,000,000)	(3,000,000)	2,000,000	(134,000,000)
Total mark-to-market adjustments - Servicing	(63,000,000)	(124,000,000)	(65,000,000)	(877,000,000)
MSR amortization	171,000,000	183,000,000	444,000,000	644,000,000
Excess spread accretion	(11,000,000)	(14,000,000)	(32,000,000)	(74,000,000)
Total amortization, net of accretion	160,000,000	169,000,000	412,000,000	570,000,000
Originations service fees(3)	18,000,000	20,000,000	45,000,000	86,000,000
Corporate/Xome related service fees	22,000,000	22,000,000	62,000,000	56,000,000
Other(4)	18,000,000	18,000,000	54,000,000	88,000,000
Total revenues - Service Related, net	432,000,000	395,000,000	1,095,000,000	1,610,000,000
Cash Flows Between Transferor and Transferee, Servicing Fees	$ 175,000,000	$ 172,000,000	$ 528,000,000	$ 488,000,000