Business Purpose Loans - Narrative (Details) $ in Millions	12 Months Ended
Dec. 31, 2022 USD ($)
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]
Amount of investments with original maturities of of 30 years (as a percent)	1.00%
Commitment To Fund Residential Bridge Loan
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]
Other commitment	$ 904
LIBOR
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]
Variable rate (as a percent)	37.00%
SOFR
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]
Variable rate (as a percent)	53.00%
Fixed Rate
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]
Variable rate (as a percent)	10.00%
Minimum \| Bridge Loans
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]
Original maturity (in months)	6 months
Maximum \| Bridge Loans
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]
Original maturity (in months)	36 months

Real Estate Owned, Held-for-Investment, Original Maturity, Term

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Real Estate Owned, Held-for-Investment, Original Maturity, Variable Rate

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Real Estate Owned, Held-for-Investment, Percent With Original Maturities Of Thirty Years

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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.

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Minimum amount of other commitment not otherwise specified in the taxonomy. Excludes commitments explicitly modeled in the taxonomy, including but not limited to, long-term and short-term purchase commitments, recorded and unrecorded purchase obligations, supply commitments, registration payment arrangements, leases, debt, product warranties, guarantees, environmental remediation obligations, and pensions.

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