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Derivatives Volume of Activity (Details) - USD ($) $ in Thousands | 12 Months Ended |
--- | --- | ---
Dec. 31, 2021 | Dec. 31, 2020
Not Designated as Hedging Instrument, Economic Hedge | Interest rate swaptions |  |
Derivative [Line Items] |  |
Derivative, Notional Amount | $ (500,000) | $ (1,250,000)
Additions | (500,000) |
Settlements, Terminations, or Pair-Offs | (1,250,000) |
Not Designated as Hedging Instrument, Economic Hedge | U.S. Treasury futures | Short position |  |
Derivative [Line Items] |  |
Derivative, Notional Amount | (3,890,000) | (825,000)
Additions | (15,880,000) |
Settlements, Terminations, or Pair-Offs | (12,815,000) |
Not Designated as Hedging Instrument, Economic Hedge | Options on U.S. Treasury futures | Long position |  |
Derivative [Line Items] |  |
Derivative, Notional Amount | 0 | (500,000)
Additions | (2,350,000) |
Settlements, Terminations, or Pair-Offs | (2,850,000) |
Not Designated as Hedging Instrument, Trading | TBA securities | Long position |  |
Derivative [Line Items] |  |
Derivative, Notional Amount | (1,530,000) | $ (1,515,000)
Additions | (22,920,000) |
Settlements, Terminations, or Pair-Offs | $ (22,905,000) |

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- Definition Aggregate notional amount entered into in the period specified by the derivative(s). Expressed as an absolute value. + References No definition available. + Details
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