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Securities, at Fair Value - Narrative (Details) | 12 Months Ended |  |  |  |  |  |  |
--- | --- | --- | --- | --- | --- | --- | --- | ---
Dec. 31, 2023 USD ($) | Dec. 31, 2022 USD ($) option | Dec. 31, 2021 USD ($) | Oct. 31, 2023 | Sep. 30, 2023 USD ($) | Jun. 30, 2023 USD ($) | Mar. 31, 2023 USD ($) | Sep. 30, 2022 USD ($) | Jun. 30, 2022 USD ($) | Mar. 31, 2022 USD ($)
Debt Securities, Available-for-sale [Line Items] |  |  |  |  |  |  |  |  |  |  |
Securities, at fair value | [1] | $ 746,090,000 | $ 333,364,000 |  |  |  |  |  |  |  |
Allowance for credit loss |  | 20,451,000 | 35,314,000 | $ 39,447,000 |  | $ 28,557,000 | $ 31,035,000 | $ 33,062,000 | $ 37,192,000 | $ 36,927,000 | $ 35,457,000
Securities, at fair value |  |  |  |  |  |  |  |  |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |  |  |  |  |  |  |  |  |
Mortgage and asset backed securities |  | 79,900,000 | 97,900,000 |  |  |  |  |  |  |  |
Amortized costs |  | 74,200,000 | 86,400,000 |  |  |  |  |  |  |  |
Gross unrealized gains |  | $ 5,700,000 | $ 11,500,000 |  |  |  |  |  |  |  |
Weighted average yield (in percent) |  | 17.00% | 14.30% |  |  |  |  |  |  |  |
Weighted average to maturity |  | 1 year 10 months 2 days | 9 months 18 days |  |  |  |  |  |  |  |
Number of options to extend maturity | option |  |  | 1 |  |  |  |  |  |  |  |
Optional extension period |  |  | 2 years |  |  |  |  |  |  |  |
Step up in coupon rate (in percent) |  |  |  |  | 0.75% |  |  |  |  |  |
CRT Securities |  |  |  |  |  |  |  |  |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |  |  |  |  |  |  |  |  |
Debt securities |  | $ 83,200,000 | $ 79,200,000 |  |  |  |  |  |  |  |
Securities, at fair value |  | 51,200,000 | 48,600,000 |  |  |  |  |  |  |  |
Debt securities sold |  |  | 15,700,000 |  |  |  |  |  |  |  |
Realized gain |  |  | 84,000 |  |  |  |  |  |  |  |
Gross unrealized losses |  | 0 | 1,200,000 |  |  |  |  |  |  |  |
Non-Agency MBS |  |  |  |  |  |  |  |  |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |  |  |  |  |  |  |  |  |
Securities, at fair value |  | 23,800,000 | 24,600,000 |  |  |  |  |  |  |  |
Gross unrealized losses |  | 128,000 | 0 |  |  |  |  |  |  |  |
Residential Mortgage Securities |  |  |  |  |  |  |  |  |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |  |  |  |  |  |  |  |  |
Debt securities sold |  | 18,200,000 |  | 0 |  |  |  |  |  |  |
Realized gain |  | 908,000 |  |  |  |  |  |  |  |  |
Gross unrealized losses |  | 0 |  |  |  |  |  |  |  |  |
Allowance for credit loss |  | $ 0 | $ 0 | $ 0 |  |  |  |  |  |  |
[1] | See Note 6 for information regarding the Company’s pledged assets.

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