Investment in Securities (Unrealized Loss Positions Securities) (Details) - USD ($) $ in Thousands	Jun. 30, 2022	Dec. 31, 2021
Securities, Available-for-sale [Line Items]
Fair Value, Less than 12 Months	$ 1,117,144	$ 1,094,937
Unrealized Losses, Less than 12 Months	(99,573)	(16,006)
Fair Value, Greater than 12 Months	289,555	44,888
Unrealized Losses, Greater than 12 Months	(38,377)	(6,414)
Fair Value, Total	1,406,699	1,139,825
Unrealized Loss, Total	(137,950)	(22,420)
Agency RMBS
Securities, Available-for-sale [Line Items]
Fair Value, Less than 12 Months	997,780	1,083,017
Unrealized Losses, Less than 12 Months	(90,856)	(15,190)
Fair Value, Greater than 12 Months	268,936	39,124
Unrealized Losses, Greater than 12 Months	(32,771)	(1,815)
Fair Value, Total	1,266,716	1,122,141
Unrealized Loss, Total	(123,627)	(17,005)
Non-Agency RMBS
Securities, Available-for-sale [Line Items]
Fair Value, Less than 12 Months	86,548	11,296
Unrealized Losses, Less than 12 Months	(5,858)	(802)
Fair Value, Greater than 12 Months	3,999	4,462
Unrealized Losses, Greater than 12 Months	(173)	(1,850)
Fair Value, Total	90,547	15,758
Unrealized Loss, Total	(6,031)	(2,652)
CLOs
Securities, Available-for-sale [Line Items]
Fair Value, Less than 12 Months	6,692	624
Unrealized Losses, Less than 12 Months	(427)	(14)
Fair Value, Greater than 12 Months	16,620	1,302
Unrealized Losses, Greater than 12 Months	(5,348)	(2,749)
Fair Value, Total	23,312	1,926
Unrealized Loss, Total	(5,775)	$ (2,763)
Other Securities
Securities, Available-for-sale [Line Items]
Fair Value, Less than 12 Months	26,124
Unrealized Losses, Less than 12 Months	(2,432)
Fair Value, Greater than 12 Months	0
Unrealized Losses, Greater than 12 Months	(85)
Fair Value, Total	26,124
Unrealized Loss, Total	$ (2,517)