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Residential Mortgage Securities and MSR Related Assets (Interest Income) (Details) - USD ($) $ in Thousands | 9 Months Ended | 12 Months Ended
--- | --- | ---
Sep. 30, 2018 | Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
Debt Securities, Available-for-sale [Line Items] |  |  |  |
Interest income |  | $ 54,137 | $ 274,554 | $ 322,475
Agency MBS |  |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |  |
Coupon interest |  | 14,038 | 82,446 | 88,233
Effective yield adjustment |  | (5,186) | (26,545) | (25,930)
Interest income |  | 8,852 | 55,901 | 62,303
Legacy Non-Agency MBS |  |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |  |
Coupon interest |  | 18,263 | 87,024 | 109,714
Effective yield adjustment |  | 10,565 | 59,622 | 69,309
Interest income |  | 28,828 | 146,646 | 179,023
Accretion income | $ 2,700 |  | 14,500 |
RPL/NPL MBS |  |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |  |
Coupon interest |  | 8,376 | 53,086 | 46,339
Effective yield adjustment |  | 560 | 338 | 1,434
Interest income |  | 8,936 | 53,424 | 47,773
Accretion income | $ 1,400 |  | 329 |
CRT securities |  |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |  |
Coupon interest |  | 7,010 | 20,532 | 30,628
Effective yield adjustment |  | 511 | (1,949) | 2,748
Interest income |  | 7,521 | 18,583 | 33,376
MSR related assets |  |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |  |
Coupon interest |  | 25,970 | 52,644 | 27,174
Effective yield adjustment |  | 9,987 | 3 | 1,246
Interest income |  | $ 35,957 | $ 52,647 | $ 28,420

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- Definition Accretion Income + References No definition available. + Details
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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=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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