Segment Information - Financial Information (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021	Dec. 31, 2021
Revenues:
Service related, net	$ 460	$ (8)	$ 1,215	$ 572
Net (loss) gain on mortgage loans held for sale	139	582	436	1,261
Total revenues	599	574	1,651	1,833
Total expenses	328	425	666	879
Other income (expenses)
Interest income	50	51	86	97
Interest expense	(111)	(119)	(217)	(245)
Other expense, net	(5)	486	217	486
Total other (expenses) income, net	(66)	418	86	338
Income (loss) from continuing operations before income tax expense (benefit)	205	567	1,071	1,292
Depreciation and amortization for property and equipment and intangible assets from continuing operations	9	16	20	31
Total assets	12,895	23,308	12,895	23,308	$ 14,204
Gain (Loss) on Disposition of Assets			(223)
Operating Segments | Servicing
Revenues:
Service related, net	414	(92)	1,115	349
Net (loss) gain on mortgage loans held for sale	(19)	197	(4)	324
Total revenues	395	105	1,111	673
Total expenses	143	121	266	231
Other income (expenses)
Interest income	35	25	54	48
Interest expense	(61)	(65)	(115)	(136)
Other expense, net	0	0	0	0
Total other (expenses) income, net	(26)	(40)	(61)	(88)
Income (loss) from continuing operations before income tax expense (benefit)	226	(56)	784	354
Depreciation and amortization for property and equipment and intangible assets from continuing operations	5	7	10	12
Total assets	9,645	15,973	9,645	15,973
Operating Segments | Originations
Revenues:
Service related, net	24	45	66	88
Net (loss) gain on mortgage loans held for sale	158	385	440	937
Total revenues	182	430	506	1,025
Total expenses	126	226	300	457
Other income (expenses)
Interest income	15	26	32	49
Interest expense	(10)	(23)	(22)	(48)
Other expense, net	0	0	0	0
Total other (expenses) income, net	5	3	10	1
Income (loss) from continuing operations before income tax expense (benefit)	61	207	216	569
Depreciation and amortization for property and equipment and intangible assets from continuing operations	5	6	9	10
Total assets	1,381	4,582	1,381	4,582
Corporate/Other
Revenues:
Service related, net	22	39	34	135
Net (loss) gain on mortgage loans held for sale	0	0	0	0
Total revenues	22	39	34	135
Total expenses	59	78	100	191
Other income (expenses)
Interest income	0	0	0	0
Interest expense	(40)	(31)	(80)	(61)
Other expense, net	(5)	486	217	486
Total other (expenses) income, net	(45)	455	137	425
Income (loss) from continuing operations before income tax expense (benefit)	(82)	416	71	369
Depreciation and amortization for property and equipment and intangible assets from continuing operations	(1)	3	1	9
Total assets	$ 1,869	$ 2,753	$ 1,869	$ 2,753