Segment Information - Financial Information (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021	Dec. 31, 2021
Revenues:
Service related, net	$ 395	$ 288	$ 1,610	$ 860
Net (loss) gain on mortgage loans held for sale	115	572	551	1,833
Total revenues	510	860	2,161	2,693
Total expenses	316	402	982	1,281
Other income (expenses)
Interest income	83	66	169	163
Interest expense	(104)	(118)	(321)	(363)
Other expense, net	(20)	8	197	494
Total other (expenses) income, net	(41)	(44)	45	294
Income from continuing operations before income tax expense	153	414	1,224	1,706
Depreciation and amortization for property and equipment and intangible assets from continuing operations	9	14	29	45
Total assets	12,815	21,661	12,815	21,661	$ 14,204
Gain (Loss) on Disposition of Assets			(223)
Operating Segments | Servicing
Revenues:
Service related, net	353	209	1,468	558
Net (loss) gain on mortgage loans held for sale	(21)	142	(25)	466
Total revenues	332	351	1,443	1,024
Total expenses	147	128	413	359
Other income (expenses)
Interest income	71	39	125	87
Interest expense	(53)	(65)	(168)	(201)
Other expense, net	0	0	0	0
Total other (expenses) income, net	18	(26)	(43)	(114)
Income from continuing operations before income tax expense	203	197	987	551
Depreciation and amortization for property and equipment and intangible assets from continuing operations	6	11	16	23
Total assets	9,703	14,560	9,703	14,560
Operating Segments | Originations
Revenues:
Service related, net	20	44	86	132
Net (loss) gain on mortgage loans held for sale	136	430	576	1,367
Total revenues	156	474	662	1,499
Total expenses	112	208	412	665
Other income (expenses)
Interest income	12	27	44	76
Interest expense	(11)	(22)	(33)	(70)
Other expense, net	0	0	0	0
Total other (expenses) income, net	1	5	11	6
Income from continuing operations before income tax expense	45	271	261	840
Depreciation and amortization for property and equipment and intangible assets from continuing operations	5	8	14	18
Total assets	1,252	4,949	1,252	4,949
Corporate/Other
Revenues:
Service related, net	22	35	56	170
Net (loss) gain on mortgage loans held for sale	0	0	0	0
Total revenues	22	35	56	170
Total expenses	57	66	157	257
Other income (expenses)
Interest income	0	0	0	0
Interest expense	(40)	(31)	(120)	(92)
Other expense, net	(20)	8	197	494
Total other (expenses) income, net	(60)	(23)	77	402
Income from continuing operations before income tax expense	(95)	(54)	(24)	315
Depreciation and amortization for property and equipment and intangible assets from continuing operations	(2)	(5)	(1)	4
Total assets	$ 1,860	$ 2,152	$ 1,860	$ 2,152