Note 7 - Offsetting Assets and Liabilities - Offsetting Liabilities (Details) - Liability [Member] - USD ($) $ in Thousands	Sep. 30, 2025	Dec. 31, 2024
Gross amount, recognized	$ 8,009,927	$ 5,025,875
Gross Amount, offset	0	0
Net Amount	8,009,927	5,025,875
Gross Amount, not recognized	(7,980,621)	(5,002,725)
Gross amount, not offset	(26,887)	(23,098)
Net amount, after deduction	2,419	52
Repurchase Agreements [Member]
Gross amount, recognized	8,006,978	5,025,543
Gross Amount, offset	0	0
Net Amount	8,006,978	5,025,543
Gross Amount, not recognized	(7,980,621)	(5,002,725)
Gross amount, not offset	(26,357)	(22,818)
Net amount, after deduction	0	0
Interest Rate Swap [Member]
Gross amount, recognized	2,267
Gross Amount, offset	0
Net Amount	2,267
Gross Amount, not recognized	0
Gross amount, not offset	0
Net amount, after deduction	2,267
TBA Contracts [Member]
Gross amount, recognized	682	332
Gross Amount, offset	0	0
Net Amount	682	332
Gross Amount, not recognized	0	0
Gross amount, not offset	(530)	(280)
Net amount, after deduction	$ 152	$ 52