Advances and Other Receivables - Schedule of Accounts Receivable (Details) - USD ($) $ in Millions	Mar. 31, 2022	Dec. 31, 2021	Mar. 31, 2021	Dec. 31, 2020
Receivables [Abstract]
Servicing advances, net of $16 and $19 purchase discount, respectively	$ 1,075	$ 1,263
Receivables from agencies, investors and prior servicers, net of $8 and $12 purchase discount, respectively	121	132
Reserves	(152)	(167)
Total advances and other receivables, net	1,044	1,228
Servicing advances discount	16	19	$ 63	$ 72
Receivables discount	$ 8	$ 12	$ 20	$ 21