Financing Agreements - Borrowings Under Repurchase Agreement And Associated Assets Pledged as Collateral (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021
Asset Pledged as Collateral with Right
Assets Sold under Agreements to Repurchase [Line Items]
Fair value of securities pledged as collateral under financing agreements	$ 8,506,310	$ 8,019,405
Mark-to-market financing agreements secured by residential whole loans \| Asset Pledged as Collateral with Right
Assets Sold under Agreements to Repurchase [Line Items]
Fair value of securities pledged as collateral under financing agreements	1,902,616	2,629,919
Mark-to-market financing agreements secured by residential whole loans \| Fair Value
Assets Sold under Agreements to Repurchase [Line Items]
Carrying Value	$ 1,966,735	$ 2,391,602
Weighted average haircut (percent)	18.56%	25.27%
Mark-to-market financing agreements secured by residential whole loans \| Fair Value \| Asset Pledged as Collateral with Right
Assets Sold under Agreements to Repurchase [Line Items]
Fair value of securities pledged as collateral under financing agreements	$ 2,470,746	$ 3,301,288
Mark-to-market financing agreements secured by securities at fair value \| Fair Value
Assets Sold under Agreements to Repurchase [Line Items]
Carrying Value	$ 142,887	$ 159,148
Weighted average haircut (percent)	37.17%	37.00%
Mark-to-market financing agreements secured by securities at fair value \| Fair Value \| Asset Pledged as Collateral with Right
Assets Sold under Agreements to Repurchase [Line Items]
Fair value of securities pledged as collateral under financing agreements	$ 227,407	$ 256,685
Mark-to-market financing agreements secured by real estate owned \| Asset Pledged as Collateral with Right
Assets Sold under Agreements to Repurchase [Line Items]
Fair value of securities pledged as collateral under financing agreements	86,903	90,445
Mark-to-market financing agreements secured by real estate owned \| Fair Value
Assets Sold under Agreements to Repurchase [Line Items]
Carrying Value	$ 15,169	$ 11,549
Weighted average haircut (percent)	51.35%	58.46%
Mark-to-market financing agreements secured by real estate owned \| Fair Value \| Asset Pledged as Collateral with Right
Assets Sold under Agreements to Repurchase [Line Items]
Fair value of securities pledged as collateral under financing agreements	$ 39,357	$ 34,606
Non-mark-to-market financing secured by residential whole loans \| Fair Value
Assets Sold under Agreements to Repurchase [Line Items]
Carrying Value	$ 1,096,544	$ 928,055
Weighted average haircut (percent)	19.24%	29.98%
Non-mark-to-market financing secured by residential whole loans \| Fair Value \| Asset Pledged as Collateral with Right
Assets Sold under Agreements to Repurchase [Line Items]
Fair value of securities pledged as collateral under financing agreements	$ 1,409,574	$ 1,420,283
Non-mark-to-market financing secured by real estate owned \| Fair Value
Assets Sold under Agreements to Repurchase [Line Items]
Carrying Value	$ 8,305	$ 11,485
Weighted average haircut (percent)	61.92%	61.28%
Non-mark-to-market financing secured by real estate owned \| Fair Value \| Asset Pledged as Collateral with Right
Assets Sold under Agreements to Repurchase [Line Items]
Fair value of securities pledged as collateral under financing agreements	$ 25,749	$ 29,894

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

Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef
-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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