Note 9 - Investments - Unrealized Losses (Details) $ in Thousands	Sep. 30, 2026 USD ($)	Dec. 31, 2025 USD ($)
Number of securities	319	205
Less than twelve months, unrealized losses	$ (18,174)	$ (1,313)
Less than twelve months, fair value	375,253	184,246
Twelve months or more, unrealized losses	(16,221)	(10,686)
Twelve months or more, fair value	111,655	122,109
Unrealized losses	(34,395)	(11,999)
Fair value	$ 486,908	$ 306,355
US Government Agencies Debt Securities [Member]
Number of securities	7	5
Less than twelve months, unrealized losses	$ (937)	$ (10)
Less than twelve months, fair value	15,933	5,990
Twelve months or more, unrealized losses	(755)	(124)
Twelve months or more, fair value	6,745	14,375
Unrealized losses	(1,692)	(134)
Fair value	$ 22,678	$ 20,365
Collateralized Mortgage-Backed Securities [Member]
Number of securities	153	72
Less than twelve months, unrealized losses	$ (14,064)	$ (755)
Less than twelve months, fair value	240,133	92,185
Twelve months or more, unrealized losses	(2,872)	(1,362)
Twelve months or more, fair value	23,391	28,712
Unrealized losses	(16,936)	(2,117)
Fair value	$ 263,524	$ 120,897
US States and Political Subdivisions Debt Securities [Member]
Number of securities	66	51
Less than twelve months, unrealized losses	$ (1,990)	$ (14)
Less than twelve months, fair value	17,655	1,481
Twelve months or more, unrealized losses	(10,091)	(5,743)
Twelve months or more, fair value	31,311	37,029
Unrealized losses	(12,081)	(5,757)
Fair value	$ 48,966	$ 38,510
Corporate Debt Securities [Member]
Number of securities	84	70
Less than twelve months, unrealized losses	$ (1,121)	$ (483)
Less than twelve months, fair value	33,595	25,381
Twelve months or more, unrealized losses	(2,491)	(3,457)
Twelve months or more, fair value	40,220	41,993
Unrealized losses	(3,612)	(3,940)
Fair value	$ 73,815	$ 67,374
Collateralized Mortgage Obligations [Member]
Number of securities	9	7
Less than twelve months, unrealized losses	$ (62)	$ (51)
Less than twelve months, fair value	67,937	59,209
Twelve months or more, unrealized losses	(12)	0
Twelve months or more, fair value	9,988	0
Unrealized losses	(74)	(51)
Fair value	$ 77,925	$ 59,209

Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for more than 12 months, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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