Mortgage-Backed Securities - Unrealized Gain (Loss) on Investments (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2023	Mar. 31, 2022
Investments [Line Items]
Unrealized gain (loss) on investments, net	$ 57,120	$ (111,251)
Residential Mortgage Backed Securities [Member]
Investments [Line Items]
Debt Securities, Trading, Unrealized Gain (Loss)	55,779	(110,201)
Commercial Mortgage Backed Securities [Member]
Investments [Line Items]
Debt Securities, Trading, Unrealized Gain (Loss)	237	0
Interest-Only-Strip [Member]
Investments [Line Items]
Debt Securities, Trading, Unrealized Gain (Loss)	1,092	(1,130)
Asset-backed Securities, Securitized Loans and Receivables
Investments [Line Items]
Unrealized gain (loss) on other investments	$ 12	$ 80

Unrealized gain (loss) on other investments resulting from change in fair value during the period recorded within net income.

No definition available.

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- Definition

Amount of unrealized gain (loss) on investment in debt security measured at fair value with change in fair value recognized in net income (trading).

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 9
-Subparagraph (e)
-URI https://asc.fasb.org/extlink&oid=126970911&loc=d3e27357-111563

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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 of unrealized gain (loss) on investment.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI https://asc.fasb.org/extlink&oid=126954810&loc=d3e3602-108585

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