Investment in Securities (Summary of Investment Income) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024
Securities, Available-for-sale [Line Items]
Interest Income	$ 122,846	$ 107,281	$ 354,230	$ 309,272
Agency RMBS
Securities, Available-for-sale [Line Items]
Coupon Interest	3,342	5,673	10,702	21,470
Net Amortization	(470)	(239)	(850)	(2,109)
Interest Income	2,872	5,434	9,852	19,361
Non-Agency RMBS and CMBS
Securities, Available-for-sale [Line Items]
Coupon Interest	23,148	7,663	57,825	22,468
Net Amortization	(11,412)	(1,053)	(29,820)	(2,460)
Interest Income	11,736	6,610	28,005	20,008
CLOs
Securities, Available-for-sale [Line Items]
Coupon Interest	2,940	5,719	8,268	11,333
Net Amortization	(389)	(1,800)	(2,519)	(3,280)
Interest Income	2,551	3,919	5,749	8,053
Other Securities
Securities, Available-for-sale [Line Items]
Coupon Interest	6,299	7,934	20,027	22,838
Net Amortization	(3,041)	293	(6,715)	(5,442)
Interest Income	3,258	8,227	13,312	17,396
Securities Investment [Member]
Securities, Available-for-sale [Line Items]
Coupon Interest	35,729	26,989	96,822	78,109
Net Amortization	(15,312)	(2,799)	(39,904)	(13,291)
Interest Income	$ 20,417	$ 24,190	$ 56,918	$ 64,818