Securities, at Fair Value - Interest Income (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Debt Securities, Available-for-sale [Line Items]
Interest income	$ 5,612	$ 10,629	$ 16,181	$ 42,433
Residential Mortgage Securities
Debt Securities, Available-for-sale [Line Items]
Coupon interest	1,308	931	3,258	3,161
Effective yield adjustment	699	1,364	2,971	11,958
Interest income	2,007	2,295	6,229	15,119
MSR-related assets
Debt Securities, Available-for-sale [Line Items]
Coupon interest	2,015	1,595	4,591	6,044
Effective yield adjustment	1,590	6,739	5,361	21,270
Interest income	$ 3,605	8,334	$ 9,952	27,314
Accretion Income		$ 4,000		12,400
RPL/NPL MBS
Debt Securities, Available-for-sale [Line Items]
Accretion Income				$ 8,800

Accretion Income

No definition available.

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- Definition

Represents the coupon interest income derived from securities backed by a pool of mortgages or trust deeds.

+ References

No definition available.

+ Details

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- Definition

Represents the following effective yield adjustments pertaining to mortgage backed securities. (1) For Agency MBS, this reflects net premium amortization and discount accretion based on actual prepayment activity. (2) For Non-Agency MBS, this is the difference between the net income calculated using the net yield, which is based on management's estimates of future cash flows, less the current coupon yield.

+ References

No definition available.

+ Details

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- Definition

Amount of operating interest income, including amortization and accretion of premiums and discounts, on securitized, pass-through debt securities collateralized by real estate mortgage loans.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04.2)
-URI https://asc.fasb.org/extlink&oid=120399700&loc=SL114874048-224260

+ 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

No definition available.

+ Details

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- Details

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- Details

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