Segment Information - Financial Information (Details) - USD ($) $ in Millions	3 Months Ended			9 Months Ended
	Sep. 30, 2021	Jun. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Revenues:
Service related, net	$ 288		$ 218	$ 860	$ 151
Net gain on mortgage loans held for sale	572		645	1,833	1,594
Total revenues	860		863	2,693	1,745
Total expenses	402		455	1,281	1,277
Other income (expenses)
Interest income	66		17	163	114
Interest expense	(118)		(128)	(363)	(394)
Other income, net	8		(51)	494	(50)
Total other (expenses) income, net	(44)		(162)	294	(330)
Income (loss) from continuing operations before income tax expense (benefit)	414		246	1,706	138
Depreciation and amortization for property and equipment and intangible assets from continuing operations	14		19	45	55
Total assets	21,661		21,755	21,661	21,755	$ 24,165
Assets of discontinued operations	3,722			3,722		5,347
Disposal Group, Disposed of by Sale, Not Discontinued Operations | Title Business
Other income (expenses)
Disposal Group, Not Discontinued Operation, Gain (Loss) on Disposal		$ 487
Discontinued Operations, Held-for-sale or Disposed of by Sale [Member] | Champion Mortgage [Member]
Other income (expenses)
Assets of discontinued operations	3,722			3,722		$ 5,347
Operating Segments | Servicing
Revenues:
Service related, net	209		83	558	(237)
Net gain on mortgage loans held for sale	142		40	466	119
Total revenues	351		123	1,024	(118)
Total expenses	128		123	359	354
Other income (expenses)
Interest income	39		1	87	44
Interest expense	(65)		(68)	(201)	(195)
Other income, net	0		0	0	0
Total other (expenses) income, net	(26)		(67)	(114)	(151)
Income (loss) from continuing operations before income tax expense (benefit)	197		(67)	551	(623)
Depreciation and amortization for property and equipment and intangible assets from continuing operations	11		6	23	14
Total assets	14,560		14,707	14,560	14,707
Operating Segments | Originations
Revenues:
Service related, net	44		27	132	68
Net gain on mortgage loans held for sale	430		605	1,367	1,475
Total revenues	474		632	1,499	1,543
Total expenses	208		195	665	528
Other income (expenses)
Interest income	27		16	76	69
Interest expense	(22)		(15)	(70)	(55)
Other income, net	0		0	0	0
Total other (expenses) income, net	5		1	6	14
Income (loss) from continuing operations before income tax expense (benefit)	271		438	840	1,029
Depreciation and amortization for property and equipment and intangible assets from continuing operations	8		5	18	12
Total assets	4,949		4,250	4,949	4,250
Corporate/Other
Revenues:
Service related, net	35		108	170	320
Net gain on mortgage loans held for sale	0		0	0	0
Total revenues	35		108	170	320
Total expenses	66		137	257	395
Other income (expenses)
Interest income	0		0	0	1
Interest expense	(31)		(45)	(92)	(144)
Other income, net	8		(51)	494	(50)
Total other (expenses) income, net	(23)		(96)	402	(193)
Income (loss) from continuing operations before income tax expense (benefit)	(54)		(125)	315	(268)
Depreciation and amortization for property and equipment and intangible assets from continuing operations	(5)		8	4	29
Total assets	$ 2,152		$ 2,798	$ 2,152	$ 2,798