Indebtedness - Narrative (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Debt Instrument [Line Items]
Interest Expense	$ 187	$ 122	$ 357	$ 232
Advance Facilities | Servicing
Debt Instrument [Line Items]
Short-Term Debt, Weighted Average Interest Rate, over Time	7.70%	7.50%	7.70%	7.40%
Warehouse & MSR Facilities
Debt Instrument [Line Items]
Short-Term Debt, Weighted Average Interest Rate, over Time	7.80%	7.40%	7.90%	7.20%
Unsecured Senior Notes
Debt Instrument [Line Items]
Maximum percentage redeemable on unsecured debt			40.00%
Repayments of debt			$ 0	$ 0
Amount of principal amount outstanding repaid			$ 0	$ 0