Securities, at Fair Value - Interest Income (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Debt Securities, Available-for-sale [Line Items]
Interest Income, Securities, Mortgage-Backed	$ 28,921	$ 56,690	$ 90,094
Residential Mortgage Securities
Debt Securities, Available-for-sale [Line Items]
Coupon interest	4,793	4,076	47,686
Effective yield adjustment	3,143	13,265	6,450
Interest Income, Securities, Mortgage-Backed	7,936	17,341	54,136
MSR-related assets
Debt Securities, Available-for-sale [Line Items]
Coupon interest	6,610	7,462	25,970
Effective yield adjustment	14,374	31,887	9,987
Interest Income, Securities, Mortgage-Backed	20,984	39,349	$ 35,957
Accretion income	$ 7,800	20,500
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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