Indebtedness - Narrative (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2023	Mar. 31, 2022
Debt Instrument [Line Items]
Interest Expense	$ 110	$ 106
Advance Facilities \| Servicing
Debt Instrument [Line Items]
Short-Term Debt, Weighted Average Interest Rate, over Time	7.20%	2.40%
Warehouse & MSR Facilities
Debt Instrument [Line Items]
Short-Term Debt, Weighted Average Interest Rate, over Time	7.00%	2.10%
Debt
Debt Instrument [Line Items]
Interest Expense	$ 99	$ 86
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

Debt Instrument, Debt Redemption, Amount Of Principal Redeemed

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- Definition

Maximum percentage redeemable of aggregate principal on unsecured debt with the net proceeds of certain equity offerings at a fixed redemption prices, plus accrued and unpaid interest and additional interest, if any, to the redemption dates, subject to compliance with certain conditions.

+ References

No definition available.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Amount of the cost of borrowed funds accounted for as interest expense.

+ References

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- Definition

The cash outflow during the period from the repayment of aggregate short-term and long-term debt. Excludes payment of capital lease obligations.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
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- Definition

Weighted average interest rate of short-term debt outstanding calculated over time.

+ References

No definition available.

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