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SECURITIES - Summary of Residential Securities and CMBS (Details) $ in Thousands | 9 Months Ended
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Sep. 30, 2019 USD ($)
Debt Securities, Available-For-Sale [Line Items] |
Beginning balance | $ 92,623,788
Purchases | 51,093,826
Sales | (19,886,088)
Principal paydowns | (11,258,324)
(Amortization) / accretion | (941,881)
Fair value adjustment | 4,462,740
Ending balance | 116,094,061
Residential Securities |
Debt Securities, Available-For-Sale [Line Items] |
Beginning balance | 92,467,030
Purchases | 50,982,244
Sales | (19,793,722)
Principal paydowns | (11,215,154)
(Amortization) / accretion | (942,429)
Fair value adjustment | 4,455,241
Ending balance | 115,953,210
Commercial Securities |
Debt Securities, Available-For-Sale [Line Items] |
Beginning balance | 156,758
Purchases | 111,582
Sales | (92,366)
Principal paydowns | (43,170)
(Amortization) / accretion | 548
Fair value adjustment | 7,499
Ending balance | $ 140,851

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