Residential Loans - Characteristics of Residential Loans Held-for-Sale (Details) - Residential Loans $ in Thousands	6 Months Ended	12 Months Ended
Jun. 30, 2023 USD ($) loan	Dec. 31, 2022 USD ($) loan
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]
Number of loans \| loan	185	994
Unpaid principal balance	$ 197,272	$ 822,063
Fair value of loans	196,737	780,781
Market value of loans pledged as collateral under short-term borrowing agreements	$ 192,910	$ 775,545
Weighted average coupon (as a percent)	6.68%	5.12%
Number of loans in foreclosure \| loan	0	0
Financing Receivables, Equal to Greater than 90 Days Past Due
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]
Number of loans with 90+ day delinquencies \| loan	1	1
Unpaid principal balance of loans with 90+ day delinquencies	$ 205	$ 208
Fair value of loans with 90+ day delinquencies	$ 167	$ 170

Financing Receivable, Number Of Loans In Foreclosure

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Financing Receivable, Number Of Loans Past Due

+ References

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Loans Held-for-Sale, Weighted Average Coupon Rate

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name Regulation S-X (SX)
-Number 210
-Section 12
-Subsection 29
-Publisher SEC

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-SubTopic 310
-Name Accounting Standards Codification
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-Paragraph 1
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-Publisher FASB
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Number of mortgage loans within investment in mortgage loan on real estate by entity with substantial portion of business acquiring and holding investment real estate or interest in real estate.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name Regulation S-X (SX)
-Number 210
-Section 12
-Subsection 29
-Footnote 3
-Publisher SEC

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-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479851/948-310-S99-1

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This item represents the aggregate fair value of loans held as assets that are 90 days or more past due for which the fair value option has been elected.

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-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 28
-Subparagraph (e)(1)
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For loans held as assets for which the fair value option has been elected, this item represents the difference between the aggregate fair value and the aggregate unpaid principal balance of those loans that are 90 days or more past due.

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Fair value portion of loan receivable, including, but not limited to, mortgage loans held for investment, finance receivables held for investment, policy loans on insurance contracts.

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-Publisher FASB
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Amortized cost, after allowance for credit loss, of financing receivable. Excludes financing receivable covered under loss sharing agreement and net investment in lease.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
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This is the sum of principal amount outstanding for both securitized and unsecuritized loans of all types.

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