Financing Agreements - Borrowings Under Repurchase Agreement And Associated Assets Pledged as Collateral (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Repurchase Agreements
Fair value of securities pledged against the repurchase agreements	$ 8,057,175	$ 8,019,405
Mark-to-market financing agreements secured by residential whole loans
Repurchase Agreements
Fair value of securities pledged against the repurchase agreements	1,814,780	2,629,919
Mark-to-market financing agreements secured by residential whole loans \| Fair Value
Repurchase Agreements
Carrying Value	2,095,002	2,391,602
Fair value of securities pledged against the repurchase agreements	$ 2,632,489	$ 3,301,288
Weighted average haircut rate	18.33%	25.27%
Mark-to-market financing agreements secured by securities at fair value \| Fair Value
Repurchase Agreements
Carrying Value	$ 111,651	$ 159,148
Fair value of securities pledged against the repurchase agreements	$ 177,111	$ 256,685
Weighted average haircut rate	37.43%	37.00%
Mark-to-market financing agreements secured by real estate owned
Repurchase Agreements
Fair value of securities pledged against the repurchase agreements	$ 84,813	$ 90,445
Mark-to-market financing agreements secured by real estate owned \| Fair Value
Repurchase Agreements
Carrying Value	16,394	11,549
Fair value of securities pledged against the repurchase agreements	$ 33,367	$ 34,606
Weighted average haircut rate	48.07%	58.46%
Non-mark-to-market financing secured by residential whole loans \| Fair Value
Repurchase Agreements
Carrying Value	$ 994,494	$ 928,055
Fair value of securities pledged against the repurchase agreements	$ 1,301,685	$ 1,420,283
Weighted average haircut rate	21.43%	29.98%
Non-mark-to-market financing secured by real estate owned \| Fair Value
Repurchase Agreements
Carrying Value	$ 9,109	$ 11,485
Fair value of securities pledged against the repurchase agreements	$ 22,902	$ 29,894
Weighted average haircut rate	60.23%	61.28%

The weighted average percentage amount by which the collateral value is contractually required to exceed the loan amount on the Company's repurchase agreements borrowings.

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, after the effects of master netting arrangements, of funds outstanding borrowed in the form of a security repurchase agreement between the entity and another party for the sale and repurchase of identical or substantially the same securities at a date certain for a specified price. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

+ 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 210
-SubTopic 20
-Section 55
-Paragraph 10
-URI https://asc.fasb.org/extlink&oid=99393222&loc=SL20226008-175313

Reference 3: 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

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (c)
-URI https://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.13(1))
-URI https://asc.fasb.org/extlink&oid=126897435&loc=d3e534808-122878

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- Definition

Fair value of securities pledged as collateral against securities sold under agreement to repurchase.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 55
-Paragraph 12
-URI https://asc.fasb.org/extlink&oid=99393222&loc=SL20226013-175313

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