Investment Securities (Narrative) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Debt Securities, Available-for-sale [Line Items]
Mortgage-backed Securities Available-for-sale, Fair Value Disclosure	$ 40,900,000	$ 54,400,000
Weighted average expected constant prepayment rate	7.40%	10.90%
Debt, at fair value	$ (95,000)	$ (126,000)
Mortgage Credit Investment Fund Limited Partnership	25,000
Agency Securities [Member]
Debt Securities, Available-for-sale [Line Items]
Unamortized premium balance	1,500,000	1,800,000
TBA securities Fifteen Year and Thirty Year Securities [Member]
Debt Securities, Available-for-sale [Line Items]
Net long TBA position, at fair value	18,600,000	27,100,000
TBA, net carrying value	$ 200,000	(44,000)
Forward Settling non-Agency Securities
Debt Securities, Available-for-sale [Line Items]
Net long TBA position, at fair value		400,000
TBA, net carrying value		$ 200