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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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