Investment in Securities (Summary of Investment Income) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022		Dec. 31, 2021
Securities, Available-for-sale [Line Items]
Net Amortization	$ 13,249	$ 25,066		$ 32,578
Interest Income	370,172	282,218	[1]	175,505
Agency RMBS
Securities, Available-for-sale [Line Items]
Coupon Interest	41,414	50,032		58,495
Net Amortization	(4,406)	(10,410)		(24,642)
Interest Income	37,008	39,622		33,853
Non-Agency RMBS and CMBS
Securities, Available-for-sale [Line Items]
Coupon Interest	29,805	18,887		13,987
Net Amortization	66	267		3,423
Interest Income	29,871	19,154		17,410
CLOs
Securities, Available-for-sale [Line Items]
Coupon Interest	4,375	5,963		10,701
Net Amortization	(666)	(1,605)		(1,035)
Interest Income	3,709	4,358		9,666
Other Securities
Securities, Available-for-sale [Line Items]
Coupon Interest	23,678	20,665		17,332
Net Amortization	(6,151)	(5,876)		(5,538)
Interest Income	17,527	14,789		11,794
Securities Investment [Member]
Securities, Available-for-sale [Line Items]
Coupon Interest	99,272	95,547		100,515
Net Amortization	(11,157)	(17,624)		(27,792)
Interest Income	$ 88,115	$ 77,923		$ 72,723

[1] Conformed to current period presentation.