Principal-Only Stripped Mortgage-Backed Securities - Activity in the Company's investment in principal-only stripped MBS (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024
Mortgage-backed securities
Balance at beginning of quarter			$ 825,865
Balance at end of quarter	$ 784,958		784,958
Principal-Only-Strip MBS
Mortgage-backed securities
Balance at beginning of quarter	817,596	$ 524,576	825,865
Purchases		410,617		$ 935,356
Repayments	(46,529)	(13,336)	(84,267)	(13,452)
Amortization of purchase discounts	6,699	8,826	18,034	9,090
Valuation adjustments	7,192	(16,460)	25,326	(16,771)
Total	(13,891)	7,634	(43,360)	7,681
Balance at end of quarter	$ 784,958	$ 914,223	$ 784,958	$ 914,223

Amount of mortgage-backed asset securities measured at fair value pledged to creditors.

No definition available.

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- Definition

The amortization purchase discounts of mortgage-backed securities, measured at fair valued, pledged to creditors.

+ References

No definition available.

+ Details

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- Definition

The amount of fair value changes in mortgage-backed securities, measured at fair valued, pledged to creditors.

+ References

No definition available.

+ Details

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- Definition

The value of mortgage-backed asset securities, subsequently measured at fair value pledged to creditors, acquired or created during the current period through purchases or from transfers of financial assets.

+ References

No definition available.

+ Details

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- Definition

The amount of repayment of mortgage-backed securities, measured at fair valued, pledged to creditors.

+ References

No definition available.

+ Details

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- Definition

Amount of gain (loss) from change in value adjustments of mortgage-backed asset securities.

+ References

No definition available.

+ 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

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-13

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