Securities, at Fair Value - Residential Mortgage Securities (Details) - USD ($) $ in Thousands		Sep. 30, 2023	Dec. 31, 2022
Debt Securities, Available-for-sale [Line Items]
Fair Value	[1]	$ 723,959	$ 333,364
Agency MBS
Debt Securities, Available-for-sale [Line Items]
Principal/ Current Face		540,319	131,165
Purchase Premiums		1,824	860
Accretable Purchase Discounts		(508)	0
Discount Designated as Credit Reserve		0	0
Gross Amortized Cost		541,635	132,025
Gross Unrealized Gains		0	0
Gross Unrealized Losses		(16,623)	(325)
Net Unrealized Gain/(Loss)		(16,623)	(325)
Fair Value		525,012	131,700
Other Securities
Debt Securities, Available-for-sale [Line Items]
Principal/ Current Face		213,672	215,649
Purchase Premiums		22,015	18,344
Accretable Purchase Discounts		(5,787)	(6,272)
Discount Designated as Credit Reserve		(46,332)	(46,332)
Gross Amortized Cost		183,568	181,389
Gross Unrealized Gains		16,474	21,473
Gross Unrealized Losses		(1,095)	(1,198)
Net Unrealized Gain/(Loss)		15,379	20,275
Fair Value		198,947	201,664
Total residential mortgage securities
Debt Securities, Available-for-sale [Line Items]
Principal/ Current Face		753,991	346,814
Purchase Premiums		23,839	19,204
Accretable Purchase Discounts		(6,295)	(6,272)
Discount Designated as Credit Reserve		(46,332)	(46,332)
Gross Amortized Cost		725,203	313,414
Gross Unrealized Gains		16,474	21,473
Gross Unrealized Losses		(17,718)	(1,523)
Net Unrealized Gain/(Loss)		(1,244)	19,950
Fair Value		723,959	333,364
CRT, Fair Value Option
Debt Securities, Available-for-sale [Line Items]
Gross Unrealized Gains		1,900	131
Gross Unrealized Losses		0	(1,200)
Fair Value		51,000	48,600
Non-Agency MBS
Debt Securities, Available-for-sale [Line Items]
Gross Unrealized Gains		111	0
Gross Unrealized Losses		(960)	0
Fair Value		$ 23,000	$ 24,600

[1] See Note 6 for information regarding the Company’s pledged assets.