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Securities, at Fair Value - Residential Mortgage Securities (Details) - USD ($) $ in Thousands | Mar. 31, 2024 | Dec. 31, 2023
--- | --- | ---
Debt Securities, Available-for-sale [Line Items] |  |  |
Fair Value | [1] | $ 736,950 | $ 746,090
Agency MBS |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |
Principal/ Current Face |  | 546,647 | 554,300
Purchase Premiums |  | 1,801 | 1,824
Accretable Purchase Discounts |  | (493) | (500)
Discount Designated as Credit Reserve |  | 0 | 0
Gross Amortized Cost |  | 547,955 | 555,624
Gross Unrealized Gains |  | 2,738 | 4,355
Gross Unrealized Losses |  | (3,774) | (835)
Net Unrealized Gain/(Loss) |  | (1,036) | 3,520
Fair Value |  | 546,919 | 559,144
Other Securities |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |
Principal/ Current Face |  | 192,671 | 193,102
Purchase Premiums |  | 20,865 | 19,686
Accretable Purchase Discounts |  | (5,571) | (5,637)
Discount Designated as Credit Reserve |  | (40,514) | (40,514)
Gross Amortized Cost |  | 167,451 | 166,637
Gross Unrealized Gains |  | 22,865 | 20,437
Gross Unrealized Losses |  | (285) | (128)
Net Unrealized Gain/(Loss) |  | 22,580 | 20,309
Fair Value |  | 190,031 | 186,946
Total residential mortgage securities |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |
Principal/ Current Face |  | 739,318 | 747,402
Purchase Premiums |  | 22,666 | 21,510
Accretable Purchase Discounts |  | (6,064) | (6,137)
Discount Designated as Credit Reserve |  | (40,514) | (40,514)
Gross Amortized Cost |  | 715,406 | 722,261
Gross Unrealized Gains |  | 25,603 | 24,792
Gross Unrealized Losses |  | (4,059) | (963)
Net Unrealized Gain/(Loss) |  | 21,544 | 23,829
Fair Value |  | 736,950 | 746,090
CRT, Fair Value Option |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |
Gross Unrealized Gains |  | 2,800 | 2,300
Gross Unrealized Losses |  | 0 | 0
Fair Value |  | 51,700 | 51,200
Non-Agency MBS |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |
Gross Unrealized Gains |  | 500 | 500
Gross Unrealized Losses |  | (300) | (100)
Fair Value |  | $ 23,600 | $ 23,800
[1] | See Note 6 for information regarding the Company’s pledged assets.

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