Advances and Other Receivables - Purchase Discount (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Servicing Advances
Servicing Advances, Discount	$ 12	$ 19
Accretion of Service Advances Discount	(3)	(3)
Servicing Advances, Discount	9	16
Receivables from Agencies, Investors and Prior Servicers
Receivable with Imputed Interest, Discount	7	8
Receivable Discount, Accretion Expense	0	(4)
Receivable with Imputed Interest, Discount	$ 7	$ 12