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Securities, at Fair Value - Residential Mortgage Securities (Details) - USD ($) $ in Thousands | Dec. 31, 2023 | Dec. 31, 2022
--- | --- | ---
Debt Securities, Available-for-sale [Line Items] |  |  |
Fair Value | [1] | $ 746,090 | $ 333,364
Agency MBS |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |
Principal/ Current Face |  | 554,300 | 131,165
Purchase Premiums |  | 1,824 | 860
Accretable Purchase Discounts |  | (500) | 0
Discount Designated as Credit Reserve |  | 0 | 0
Gross Amortized Cost |  | 555,624 | 132,025
Gross Unrealized Gains |  | 4,355 | 0
Gross Unrealized Losses |  | (835) | (325)
Net Unrealized Gain/(Loss) |  | 3,520 | (325)
Fair Value |  | 559,144 | 131,700
Other Securities |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |
Principal/ Current Face |  | 193,102 | 215,649
Purchase Premiums |  | 19,686 | 18,344
Accretable Purchase Discounts |  | (5,637) | (6,272)
Discount Designated as Credit Reserve |  | (40,514) | (46,332)
Gross Amortized Cost |  | 166,637 | 181,389
Gross Unrealized Gains |  | 20,437 | 21,473
Gross Unrealized Losses |  | (128) | (1,198)
Net Unrealized Gain/(Loss) |  | 20,309 | 20,275
Fair Value |  | 186,946 | 201,664
Residential Mortgage Securities |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |
Principal/ Current Face |  | 747,402 | 346,814
Purchase Premiums |  | 21,510 | 19,204
Accretable Purchase Discounts |  | (6,137) | (6,272)
Discount Designated as Credit Reserve |  | (40,514) | (46,332)
Gross Amortized Cost |  | 722,261 | 313,414
Gross Unrealized Gains |  | 24,792 | 21,473
Gross Unrealized Losses |  | (963) | (1,523)
Net Unrealized Gain/(Loss) |  | 23,829 | 19,950
Fair Value |  | 746,090 | 333,364
CRT Securities |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |
Gross Unrealized Gains |  | 2,300 | 131
Gross Unrealized Losses |  | 0 | (1,200)
Fair Value |  | 51,200 | 48,600
Non-Agency MBS |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |
Gross Unrealized Gains |  | 474 | 0
Gross Unrealized Losses |  | (128) | 0
Fair Value |  | $ 23,800 | $ 24,600
[1] | See Note 6 for information regarding the Company’s pledged assets.

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