Repurchase Agreements - Borrowings Under Financing Arrangements and Associated Assets Pledged as Collateral (Details) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
Sep. 30, 2022	Dec. 31, 2021
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]
Outstanding Repurchase Agreements	$ 53,159
Fair Value of Loans Pledged	3,933,176	$ 3,575,601
Repurchase agreements
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]
Outstanding Repurchase Agreements	53,159
Carrying Value of Repurchase Agreements	1,215,023	554,259
Fair Value of Loans Pledged	$ 180,010
Weighted Average Months to Maturity	7 days
Residential loans
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]
Maximum Aggregate Uncommitted Principal Amount	$ 2,064,587	1,252,352
Outstanding Repurchase Agreements	1,163,408	554,784
Net Deferred Finance Costs	(1,544)	(525)
Fair Value of Loans Pledged	$ 1,439,654	$ 729,649
Weighted Average Rate	5.20%	2.79%
Weighted Average Months to Maturity	13 years 1 month 2 days	4 years 4 months 17 days
Residential loans \| Repurchase agreements
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]
Carrying Value of Repurchase Agreements	$ 1,161,864	$ 554,259
Residential loans \| Repurchase Agreement, Non Mark-to Market
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]
Outstanding Repurchase Agreements	$ 620,700	$ 15,600
Weighted Average Rate	5.32%	4.00%
Weighted Average Months to Maturity	19 years 1 month 2 days	2 years 10 days

Assets Sold under Agreements to Repurchase, Deferred Finance Costs, Net

No definition available.

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- Definition

The total amount of repossession that is available under the repurchase agreement.

+ References

No definition available.

+ Details

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- Definition

Carrying amount of assets sold under agreements to repurchase when the carrying amount (or market value, if higher than the carrying amount) of securities or other assets sold under repurchase agreements exceeds 10 percent of total assets.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(m)(1)(i))
-URI https://asc.fasb.org/extlink&oid=120395691&loc=d3e23780-122690

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(m)(1)(ii)(A)(i))
-URI https://asc.fasb.org/extlink&oid=120395691&loc=d3e23780-122690

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- Definition

Interest rate on the amount to be repaid to the counterparty to the repurchase agreement when the carrying amount (or market value, if higher than the carrying amount) of securities or other assets sold under the repurchase agreement exceeds 10 percent of total assets.

+ References

+ Details

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- Definition

Amount to be repaid to the counterparty to the repurchase agreement when the carrying amount (or market value, if higher than the carrying amount) of securities or other assets sold under the repurchase agreement exceeds 10 percent of total assets.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(m)(1)(ii)(A)(ii))
-URI https://asc.fasb.org/extlink&oid=120395691&loc=d3e23780-122690

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(m)(1)(i))
-URI https://asc.fasb.org/extlink&oid=120395691&loc=d3e23780-122690

+ Details

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- Definition

Amount of 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.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 948
-SubTopic 310
-Section S99
-Paragraph 1
-Subparagraph (SX 210.12-29(Column G))
-URI https://asc.fasb.org/extlink&oid=120402547&loc=d3e617274-123014

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- Definition

Weighted average maturity (weighted by amount of the agreement) of repurchase agreements with the counterparty, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

+ Details

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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.

+ Details

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