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v3.21.1

Mortgage-Backed Securities (Details) | 3 Months Ended |
--- | --- | ---
Mar. 31, 2021 USD ($) | Mar. 31, 2020 USD ($) | Dec. 31, 2020 USD ($)
Investments [Line Items] |  |  |  |
Debt Securities, Trading, Amortized Cost | $ 68,542,000 |  |  |
Debt Securities, Trading, Unrealized Gain | 0 |  |  |
Debt Securities, Trading, Unrealized Loss | (960,000) |  |  |
Debt Securities, Trading | 67,582,000 |  |  |
Debt Securities, Trading and Available-for-sale | 2,380,373,000 |  |  |
Proceeds from Sale of Available-for-sale Securities | 74,829,000 |  | $ 1,991,034,000 |
Debt Securities, Available-for-sale, Realized Gain (Loss) | 4,697,000 |  | 84,783,000 |
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions, Greater than or Equal to One Year |  |  |  | 2
Debt Securities, Available-for-sale, Allowance for Credit Loss | 0 |  |  |
Par value of available for sale debt security | 1,887,309,000 |  |  | $ 2,076,346,000
Debt Securities, Available-for-sale, Amortized Cost | 2,297,687,000 |  |  | 2,515,995,000
Debt Securities, Available-for-sale | 2,312,791,000 |  |  | 2,596,255,000
Par Value of Debt Security, Fair Value Option Elected | 67,692,000 |  |  |
Investments, Unamortized Premium (Discount) | 410,378,000 |  |  | 439,649,000
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax | 40,599,000 |  |  | 81,293,000
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax | (25,495,000) |  |  | (1,033,000)
Fair Value Option |  |  |  |
Investments [Line Items] |  |  |  |
Investments, Unamortized Premium (Discount) | 850,000 |  |  |
Residential Mortgage Backed Securities |  |  |  |
Investments [Line Items] |  |  |  |
Par value of available for sale debt security |  |  |  | 1,839,046,000
Debt Securities, Available-for-sale, Amortized Cost |  |  |  | 1,897,043,000
Debt Securities, Available-for-sale |  |  |  | 1,946,391,000
Investments, Unamortized Premium (Discount) |  |  |  | 57,997,000
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax |  |  |  | 49,348,000
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax |  |  |  | 0
Residential Mortgage Backed Securities | Agency MBS |  |  |  |
Investments [Line Items] |  |  |  |
Debt Securities, Trading, Amortized Cost | 68,542,000 |  |  |
Debt Securities, Trading, Unrealized Gain | 0 |  |  |
Debt Securities, Trading, Unrealized Loss | (960,000) |  |  |
Debt Securities, Trading | 67,582,000 |  |  |
Debt Securities, Trading and Available-for-sale | 1,763,737,000 |  |  |
Proceeds from Sale of Available-for-sale Securities | 74,829,000 |  | 1,817,350,000 |
Debt Securities, Available-for-sale, Realized Gain | 4,697,000 |  |  |
Debt Securities, Available-for-sale, Realized Loss |  |  | 64,094,000 |
Par value of available for sale debt security | 1,651,864,000 |  |  |
Debt Securities, Available-for-sale, Amortized Cost | 1,706,982,000 |  |  |
Debt Securities, Available-for-sale | 1,696,155,000 |  |  | 1,946,391,000
Par Value of Debt Security, Fair Value Option Elected | 67,692,000 |  |  |
Investments, Unamortized Premium (Discount) | 55,118,000 |  |  |
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax | 13,646,000 |  |  |
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax | (24,473,000) |  |  |
Residential Mortgage Backed Securities | Agency MBS | Fair Value Option |  |  |  |
Investments [Line Items] |  |  |  |
Investments, Unamortized Premium (Discount) | 850,000 |  |  |
Commercial Mortgage Backed Securities |  |  |  |
Investments [Line Items] |  |  |  |
Proceeds from Sale of Available-for-sale Securities | 0 |  |  |
Debt Securities, Available-for-sale, Realized Loss | 0 |  |  |
Debt Securities, Available-for-sale, Amortized Cost |  |  |  | 238,953,000
Debt Securities, Available-for-sale |  |  |  | 258,550,000
Investments, Unamortized Premium (Discount) |  |  |  | 3,152,000
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax |  |  |  | 19,597,000
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax |  |  |  | 0
Commercial Mortgage Backed Securities | Agency MBS |  |  |  |
Investments [Line Items] |  |  |  |
Debt Securities, Trading and Available-for-sale | 249,617,000 |  |  |
Proceeds from Sale of Available-for-sale Securities |  |  | 173,684,000 |
Debt Securities, Available-for-sale, Realized Loss |  |  | $ 20,689,000 |
Par value of available for sale debt security | 234,091,000 |  |  | 235,801,000
Debt Securities, Available-for-sale, Amortized Cost | 237,066,000 |  |  |
Debt Securities, Available-for-sale | 249,617,000 |  |  | 258,550,000
Investments, Unamortized Premium (Discount) | 2,975,000 |  |  |
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax | 12,551,000 |  |  |
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax | 0 |  |  |
Interest-Only-Strip |  |  |  |
Investments [Line Items] |  |  |  |
Debt Securities, Trading and Available-for-sale | 365,876,000 |  |  |
Par value of available for sale debt security | 0 | [1] |  | 0
Debt Securities, Available-for-sale, Amortized Cost | 352,655,000 |  |  | 378,940,000
Debt Securities, Available-for-sale | 365,876,000 |  |  | 390,039,000
Investments, Unamortized Premium (Discount) | 352,655,000 |  |  | 378,940,000
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax | 14,200,000 |  |  | 12,081,000
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax | (979,000) |  |  | (982,000)
Non-Agency MBS |  |  |  |
Investments [Line Items] |  |  |  |
Notional balance for interest only securities | 9,209,025,000 |  |  | 9,319,520,000
Debt Securities, Trading and Available-for-sale | 1,143,000 |  |  |
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value | 5,221,000 |  |  | 33,417,000
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss | $ 111,000 |  |  | $ 408,000
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions, Less than One Year | 5 |  |  | 23
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value | $ 5,029,000 |  |  | $ 2,156,000
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | $ 140,000 |  |  | $ 93,000
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions, Greater than or Equal to One Year | 8 |  |  | 5
Par value of available for sale debt security | $ 1,354,000 |  |  | $ 1,499,000
Debt Securities, Available-for-sale, Amortized Cost | 984,000 |  |  | 1,059,000
Debt Securities, Available-for-sale | 1,143,000 |  |  | 1,275,000
Investments, Unamortized Premium (Discount) | (370,000) |  |  | (440,000)
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax | 202,000 |  |  | 267,000
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax | (43,000) |  |  | (51,000)
Agency MBS |  |  |  |
Investments [Line Items] |  |  |  |
Notional balance for interest only securities | 11,097,619,000 |  |  | 11,277,908,000
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value | 1,446,354,000 |  |  | 19,266,000
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss | $ 25,019,000 |  |  | $ 399,000
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions, Less than One Year | 32 |  |  | 19
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value | $ 846,000 |  |  | $ 749,000
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | $ 224,000 |  |  | $ 133,000
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions, Greater than or Equal to One Year | 5 |  |  |
[1] | The notional balance for Agency CMBS IO and non-Agency CMBS IO was $11,097,619 and $9,209,025 respectively, as of March 31, 2021.
| December 31, 2020
| Agency RMBS |  | Agency CMBS |  | CMBS IO (1) |  | Non-Agency Other |  | Total
MBS designated as AFS: |  |  |  |  |  |  |  |  |
Par value | $ | 1,839,046 |  |  | $ | 235,801 |  |  | $ | — |  |  | $ | 1,499 |  |  | $ | 2,076,346 |
Unamortized premium (discount) | 57,997 |  |  | 3,152 |  |  | 378,940 |  |  | (440) |  |  | 439,649 |
Amortized cost | 1,897,043 |  |  | 238,953 |  |  | 378,940 |  |  | 1,059 |  |  | 2,515,995 |
Gross unrealized gain | 49,348 |  |  | 19,597 |  |  | 12,081 |  |  | 267 |  |  | 81,293 |
Gross unrealized loss | — |  |  | — |  |  | (982) |  |  | (51) |  |  | (1,033) |
Fair value | 1,946,391 |  |  | 258,550 |  |  | 390,039 |  |  | 1,275 |  |  | 2,596,255 |
MBS measured at fair value through net income: |  |  |  |  |  |  |  |
Par value | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | — |
Unamortized premium (discount) | — |  |  | — |  |  | — |  |  | — |  |  | — |
Amortized cost | — |  |  | — |  |  | — |  |  | — |  |  | — |
Gross unrealized gain | — |  |  | — |  |  | — |  |  | — |  |  | — |
Gross unrealized loss | — |  |  | — |  |  | — |  |  | — |  |  | — |
Fair value | — |  |  | — |  |  | — |  |  | — |  |  | — |
Total as of December 31, 2020 | $ | 1,946,391 |  |  | $ | 258,550 |  |  | $ | 390,039 |  |  | $ | 1,275 |  |  | $ | 2,596,255 |

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Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
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- Details
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Namespace Prefix: |
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- Details
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- Details
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- Details
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- Details
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- Details
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- Details
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