Note 25 - Regulatory Matters - Risk Based Capital Amounts and Ratios (Details) $ in Thousands		Dec. 31, 2024 USD ($)	Dec. 31, 2023 USD ($)
Total risk-based capital, actual amount	[1]	$ 943,723	$ 849,836
Total risk-based capital, actual ratio	[1]	0.1273	0.1256
Total risk-based capital, minimum for adequately capitalized amount	[1]	$ 593,201	$ 541,370
Total risk-based capital, minimum for adequately capitalized ratio	[1]	0.08	0.08
Common Equity Tier 1 risk-based capital, actual amount	[1]	$ 828,386	$ 747,376
Common Equity Tier 1 risk-based capital, actual ratio	[1]	0.1117	0.1104
Common Equity Tier 1 risk-based capital, minimum for adequately capitalized amount	[1]	$ 333,676	$ 304,521
Common Equity Tier 1 risk-based capital, minimum for adequately capitalized ratio	[1]	0.045	0.045
Tier 1 risk-based capital, actual amount	[1]	$ 854,386	$ 773,376
Tier 1 risk-based capita, actual ratio	[1]	0.1152	0.1143
Tier 1 risk-based capital, minimum for adequately capitalized amount	[1]	$ 444,901	$ 406,027
Tier 1 risk-based capital, minimum for adequately capitalized ratio	[1]	0.06	0.06
Tier 1 risk-based capital, actual amount	[1]	$ 854,386	$ 773,376
Leverage, actual amount			$ 773,376
Leverage, actual ratio		0.0994	0.0962
Leverage, minimum for adequately capitalized amount		$ 343,886	$ 321,713
Leverage, minimum for adequately capitalized ratio		0.04	0.04
Subsidiaries [Member]
Total risk-based capital, actual amount	[1]	$ 918,210	$ 823,275
Total risk-based capital, actual ratio	[1]	0.1239	0.1221
Total risk-based capital, minimum for adequately capitalized amount	[1]	$ 593,002	$ 539,609
Total risk-based capital, minimum for adequately capitalized ratio	[1]	0.08	0.08
Total risk-based capital, minimum for well capitalized amount	[1]	$ 741,252	$ 674,511
Total risk-based capital, minimum for well capitalized ratio	[1]	0.10	0.10
Common Equity Tier 1 risk-based capital, actual amount	[1]	$ 828,873	$ 746,815
Common Equity Tier 1 risk-based capital, actual ratio	[1]	0.1118	0.1107
Common Equity Tier 1 risk-based capital, minimum for adequately capitalized amount	[1]	$ 333,564	$ 303,530
Common Equity Tier 1 risk-based capital, minimum for adequately capitalized ratio	[1]	0.045	0.045
Common Equity Tier 1 risk-based capital, minimum for well capitalized amount	[1]	$ 481,814	$ 438,432
Common Equity Tier 1 risk-based capital, minimum for well capitalized ratio	[1]	0.065	0.065
Tier 1 risk-based capital, actual amount	[1]	$ 828,873	$ 746,815
Tier 1 risk-based capita, actual ratio	[1]	0.1118	0.1107
Tier 1 risk-based capital, minimum for adequately capitalized amount	[1]	$ 444,751	$ 404,707
Tier 1 risk-based capital, minimum for adequately capitalized ratio	[1]	0.06	0.06
Tier 1 risk-based capital, minimum for well capitalized amount	[1]	$ 593,002	$ 539,609
Tier 1 risk-based capital, minimum for well capitalized ratio	[1]	0.08	0.08
Tier 1 risk-based capital, actual amount	[1]	$ 828,873	$ 746,815
Leverage, actual amount		$ 828,873	$ 746,815
Leverage, actual ratio		0.0965	0.093
Leverage, minimum for adequately capitalized amount		$ 343,624	$ 321,323
Leverage, minimum for adequately capitalized ratio		0.04	0.04
Leverage, minimum for well capitalized amount		$ 429,530	$ 401,654
Leverage, minimum for well capitalized ratio		0.05	0.05

[1] Ratio is computed in relation to risk-weighted assets.