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Derivatives Volume of Activity (Details) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2020 USD ($)
Interest rate swaption |
Derivative [Line Items] |
Derivative Asset, Notional Amount | $ 1,250,000
Not Designated as Hedging Instrument, Economic Hedge | Interest rate swaps |
Derivative [Line Items] |
Derivative Asset, Notional Amount | 4,225,000
Notional Amount of Derivative Instruments Added | 2,915,000
Notional Amount of Derivative Instruments Maturing, Settled, Terminated, or Paired-Off | (7,140,000)
Derivative Asset, Notional Amount | 0
Not Designated as Hedging Instrument, Economic Hedge | Interest rate swaption |
Derivative [Line Items] |
Derivative Asset, Notional Amount | 750,000
Notional Amount of Derivative Instruments Added | 1,250,000
Notional Amount of Derivative Instruments Maturing, Settled, Terminated, or Paired-Off | (750,000)
Derivative Asset, Notional Amount | 1,250,000
Not Designated as Hedging Instrument, Economic Hedge | U.S. Treasury futures | Short position |
Derivative [Line Items] |
Derivative Liability, Notional Amount | 0
Notional Amount of Derivative Instruments Added | 5,737,600
Notional Amount of Derivative Instruments Maturing, Settled, Terminated, or Paired-Off | (4,912,600)
Derivative Liability, Notional Amount | 825,000
Not Designated as Hedging Instrument, Economic Hedge | Options on U.S. Treasury futures |
Derivative [Line Items] |
Derivative Asset, Notional Amount | 1,350,000
Notional Amount of Derivative Instruments Added | 5,650,000
Notional Amount of Derivative Instruments Maturing, Settled, Terminated, or Paired-Off | (6,500,000)
Derivative Asset, Notional Amount | 500,000
Not Designated as Hedging Instrument, Economic Hedge | TBA securities | Short position |
Derivative [Line Items] |
Derivative Liability, Notional Amount | 500,000
Notional Amount of Derivative Instruments Added | 3,017,000
Notional Amount of Derivative Instruments Maturing, Settled, Terminated, or Paired-Off | (3,517,000)
Derivative Liability, Notional Amount | 0
Not Designated as Hedging Instrument, Trading | TBA securities | Long position |
Derivative [Line Items] |
Derivative Asset, Notional Amount | 435,000
Notional Amount of Derivative Instruments Added | 15,516,000
Notional Amount of Derivative Instruments Maturing, Settled, Terminated, or Paired-Off | (14,436,000)
Derivative Asset, Notional Amount | $ 1,515,000

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