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Securities, at Fair Value (Interest Income) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Debt Securities, Available-for-sale [Line Items]
Interest income	$ 16,459	$ 58,581
Agency MBS
Debt Securities, Available-for-sale [Line Items]
Coupon interest	0	13,636
Effective yield adjustment	0	(4,775)
Interest income	0	8,861
Legacy Non-Agency MBS
Debt Securities, Available-for-sale [Line Items]
Coupon interest	14	17,282
Effective yield adjustment	670	9,406
Interest income	684	26,688
Accretion Income	670
RPL/NPL MBS
Debt Securities, Available-for-sale [Line Items]
Coupon interest	352	5,583
Effective yield adjustment	8,135	280
Interest income	8,487	5,863
Accretion Income	8,100	277
CRT securities
Debt Securities, Available-for-sale [Line Items]
Coupon interest	921	3,485
Effective yield adjustment	744	(523)
Interest income	1,665	2,962
MSR-related assets
Debt Securities, Available-for-sale [Line Items]
Coupon interest	2,405	14,207
Effective yield adjustment	3,218	0
Interest income	$ 5,623	$ 14,207

X

- Definition

Accretion Income

+ References

No definition available.

+ Details

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X

- 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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X

- 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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X

- 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 http://asc.fasb.org/extlink&oid=120399700&loc=SL114874048-224260

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X

- 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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