Note 5 - Derivative and Other Hedging Instruments - Schedule of To Be Announced Securities (Details) - Short [Member] - USD ($) $ in Thousands		Dec. 31, 2023	Dec. 31, 2022
Three Percent TBA Securities [Member]
Notional amount	[1]	$ (70,700)	$ (500,000)
Cost	[2]	(59,278)	(440,644)
Market value	[3]	(62,647)	(440,274)
Net carrying value	[4]	(3,369)	370
Five Percent TBA Securities [Member]
Notional amount	[1]	(250,000)
Cost	[2]	(242,725)
Market value	[3]	(247,657)
Net carrying value	[4]	(4,932)
Five and a Half Percent TBA Securities [Member]
Notional amount	[1]	(325,000)
Cost	[2]	(322,410)
Market value	[3]	(326,803)
Net carrying value	[4]	(4,393)
TBA Contracts [Member]
Notional amount	[1]	(645,700)	(675,000)
Cost	[2]	(624,413)	(582,912)
Market value	[3]	(637,107)	(583,419)
Net carrying value	[4]	$ (12,694)	(507)
Two Percent TBA Contract [Member]
Notional amount	[1]		(175,000)
Cost	[2]		(142,268)
Market value	[3]		(143,145)
Net carrying value	[4]		$ (877)

[1] Notional amount represents the par value (or principal balance) of the underlying Agency RMBS.

[2] Cost basis represents the forward price to be paid (received) for the underlying Agency RMBS.

[3] Market value represents the current market value of the TBA securities (or of the underlying Agency RMBS) as of period-end.

[4] Net carrying value represents the difference between the market value and the cost basis of the TBA securities as of period-end and is reported in derivative assets (liabilities), at fair value in our balance sheets