Note 3 - Investment Securities - Portfolio of Securities Available-for-sale (Details) - USD ($) $ in Thousands	Jun. 30, 2022	Dec. 31, 2021
Amortized cost	$ 731,131	$ 535,182
Gross unrealized gains	993	4,281
Gross unrealized losses	(56,183)	(4,956)
Securities available-for-sale	675,941	534,507
Allowance for investment credit losses	0	0
US Government Agencies Debt Securities [Member]
Amortized cost	58,375	50,336
Gross unrealized gains	3	649
Gross unrealized losses	(5,708)	(625)
Securities available-for-sale	52,670	50,360
Allowance for investment credit losses	0	0
Residential Mortgage-Backed Securities [Member]
Amortized cost	480,445	317,111
Gross unrealized gains	718	1,868
Gross unrealized losses	(36,883)	(2,884)
Securities available-for-sale	444,280	316,095
Allowance for investment credit losses	0	0
Commercial Mortgage-Backed Securities [Member]
Amortized cost	25,627	10,814
Gross unrealized gains	0	118
Gross unrealized losses	(2,769)	(463)
Securities available-for-sale	22,858	10,469
Allowance for investment credit losses	0	0
US States and Political Subdivisions Debt Securities [Member]
Amortized cost	158,545	145,045
Gross unrealized gains	252	1,562
Gross unrealized losses	(10,766)	(982)
Securities available-for-sale	148,031	145,625
Allowance for investment credit losses	0	0
Corporate Debt Securities [Member]
Amortized cost	5,480	8,968
Gross unrealized gains	20	81
Gross unrealized losses	(9)	0
Securities available-for-sale	5,491	9,049
Allowance for investment credit losses	0	0
Asset-Backed Securities [Member]
Amortized cost	2,165	2,563
Gross unrealized gains	0	3
Gross unrealized losses	(48)	(2)
Securities available-for-sale	2,117	2,564
Allowance for investment credit losses		0
Other Debt Obligations [Member]
Amortized cost	494	195
Gross unrealized gains	0	0
Gross unrealized losses	0	0
Securities available-for-sale	494	195
Allowance for investment credit losses	$ 0	0
Certificates of Deposit [Member]
Amortized cost		150
Gross unrealized gains		0
Gross unrealized losses		0
Securities available-for-sale		150
Allowance for investment credit losses		$ 0

Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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