Residential Mortgage Securities and MSR-Related Assets (Interest Income) (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Agency MBS
Debt Securities, Available-for-sale [Line Items]
Coupon interest	$ 24,628	$ 20,958
Effective yield adjustment	(6,187)	(5,665)
Interest income	18,441	15,293
Legacy Non-Agency MBS
Debt Securities, Available-for-sale [Line Items]
Coupon interest	24,272	28,835
Effective yield adjustment	13,144	17,201
Interest income	37,416	46,036
RPL/NPL MBS
Debt Securities, Available-for-sale [Line Items]
Coupon interest	16,443	10,053
Effective yield adjustment	142	13
Interest income	16,585	10,066
Accretion Income	148	1,200
CRT securities
Debt Securities, Available-for-sale [Line Items]
Coupon interest	6,118	8,374
Effective yield adjustment	82	1,122
Interest income	6,200	9,496
MSR-related assets
Debt Securities, Available-for-sale [Line Items]
Coupon interest	10,587	7,517
Effective yield adjustment	33	106
Interest income	$ 10,620	$ 7,623

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 http://asc.fasb.org/extlink&oid=114873765&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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