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Residential Mortgage Securities and MSR Related Assets (Purchase Discounts) (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2019 | Dec. 31, 2018
Discount Designated as Credit Reserve and OTTI | Non-Agency MBS |  |
Changes in the components of the purchase discount on Non-Agency MBS |  |
Balance at beginning of period | $ (516,116) | $ (593,227)
Impact of RMBS Issuer Settlement | 0 | 0
Accretion of discount | 0 | 0
Realized credit losses | 28,152 | 42,246
Purchases | (624) | (2,512)
Sales/Redemptions | 34,510 | 12,987
Net impairment losses recognized in earnings | (180) | (1,259)
Transfers/release of credit reserve | 17,660 | 25,649
Balance at end of period | (436,598) | (516,116)
Accretable Discount | Non-Agency MBS |  |
Changes in the components of the purchase discount on Non-Agency MBS |  |
Balance at beginning of period | (155,025) | (215,325)
Impact of RMBS Issuer Settlement | (2,077) | (14,822)
Accretion of discount | 51,696 | 70,750
Realized credit losses | 0 | 0
Purchases | (4) | 1,685
Sales/Redemptions | 32,453 | 28,336
Net impairment losses recognized in earnings | 0 | 0
Transfers/release of credit reserve | (17,660) | (25,649)
Balance at end of period | (90,617) | (155,025)
Jp Morgan Chase |  |
Changes in the components of the purchase discount on Non-Agency MBS |  |
Proceeds from legal settlements | $ 2,000 | 12,100
Lehman Brothers |  |
Changes in the components of the purchase discount on Non-Agency MBS |  |
Proceeds from legal settlements |  | $ 2,700

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