Financing Agreements - Borrowings Under Repurchase Agreement And Associated Assets Pledged as Collateral (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Repurchase Agreements
Fair value of securities pledged against the repurchase agreements	$ 8,019,405	$ 5,799,786
Mark-to-market financing agreements secured by residential whole loans
Repurchase Agreements
Fair value of securities pledged against the repurchase agreements	2,629,919	4,140,961
Mark-to-market financing agreements secured by residential whole loans \| Fair Value
Repurchase Agreements
Carrying Value	$ 2,391,602	$ 1,113,553
Weighted average haircut rate	25.27%	34.17%
Mark-to-market financing agreements secured by residential whole loans \| Fair Value \| Asset Pledged as Collateral with Right
Repurchase Agreements
Fair value of securities pledged against the repurchase agreements	$ 3,301,288	$ 1,798,813
Mark-to-market financing agreements secured by securities at fair value \| Fair Value
Repurchase Agreements
Carrying Value	$ 159,148	$ 213,915
Weighted average haircut rate	37.00%	41.16%
Mark-to-market financing agreements secured by securities at fair value \| Fair Value \| Asset Pledged as Collateral with Right
Repurchase Agreements
Fair value of securities pledged against the repurchase agreements	$ 256,685	$ 399,999
Mark-to-market financing agreements secured by real estate owned
Repurchase Agreements
Fair value of securities pledged against the repurchase agreements	90,445	49,477
Mark-to-market financing agreements secured by real estate owned \| Fair Value
Repurchase Agreements
Carrying Value	$ 11,549	$ 10,609
Weighted average haircut rate	58.46%	55.56%
Mark-to-market financing agreements secured by real estate owned \| Fair Value \| Asset Pledged as Collateral with Right
Repurchase Agreements
Fair value of securities pledged against the repurchase agreements	$ 34,606	$ 22,525
Loan Securitization \| Fair Value
Repurchase Agreements
Fair value of securities pledged against the repurchase agreements		141,900
Non-mark-to-market financing secured by residential whole loans \| Fair Value
Repurchase Agreements
Carrying Value	$ 928,055	$ 1,156,125
Weighted average haircut rate	29.98%	39.46%
Non-mark-to-market financing secured by residential whole loans \| Fair Value \| Asset Pledged as Collateral with Right
Repurchase Agreements
Fair value of securities pledged against the repurchase agreements	$ 1,420,283	$ 1,930,283
Non-mark-to-market financing secured by real estate owned \| Fair Value
Repurchase Agreements
Carrying Value	$ 11,485	$ 3,088
Weighted average haircut rate	61.28%	59.73%
Non-mark-to-market financing secured by real estate owned \| Fair Value \| Asset Pledged as Collateral with Right
Repurchase Agreements
Fair value of securities pledged against the repurchase agreements	$ 29,894	$ 7,441

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))
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
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-Section 55
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-Section S99
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
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-Section 50
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-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
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-Subparagraph (SX 210.9-03.13(1))
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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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