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Other Assets (TBA Securities) (Details) - Short | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2021 USD ($) | Sep. 30, 2021 USD ($)
TBA Securities |  |
Derivative [Line Items] |  |
Aggregate value | $ 5,400,000 | $ 5,400,000
Gain on derivative | 2,100,000 | 1,000,000
FNCL 2.0 10/21 |  |
Derivative [Line Items] |  |
Notional Amount | 420,000,000 | 420,000,000
FNCL 2.5 10/21 |  |
Derivative [Line Items] |  |
Notional Amount | $ 330,000,000 | $ 330,000,000

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