Note 3 - INVESTMENT SECURITIES - Securities in a Continuous Unrealized Loss Position (Details) - USD ($) $ in Thousands	Jun. 30, 2022	Dec. 31, 2021
Securities available for sale:
Securities available for sale, less than 12 months, fair value	$ 305,221	$ 32,980
Securities available for sale, less than 12 months, gross unrealized losses	(41,799)	(464)
Securities available for sale, 12 months or more, fair value	24,525	23,442
Securities available for sale, 12 months or more, gross unrealized losses	(4,501)	(857)
Securities available for sale, fair value	329,746	56,422
Securities available for sale, gross unrealized losses	(46,300)	(1,321)
Municipal securities.
Securities held to maturity:
Securities held to maturity, less than 12 months, fair value	68,468	1,049
Securities held to maturity, less than 12 months, gross unrealized losses	(7,786)	(1)
Securities held to maturity, 12 months or more, fair value	95,070
Securities held to maturity, 12 months or more, gross unrealized losses	(8,322)
Securities held to maturity, fair value	163,538	1,049
Securities held to maturity, gross unrealized losses	(16,108)	(1)
Securities available for sale:
Securities available for sale, less than 12 months, fair value	185,244	13,287
Securities available for sale, less than 12 months, gross unrealized losses	(37,071)	(211)
Securities available for sale, 12 months or more, fair value	3,828	1,001
Securities available for sale, 12 months or more, gross unrealized losses	(1,140)	(4)
Securities available for sale, fair value	189,072	14,288
Securities available for sale, gross unrealized losses	(38,211)	(215)
U.S. treasuries and govt. sponsored agency securities
Securities available for sale:
Securities available for sale, less than 12 months, fair value	16,574	9,802
Securities available for sale, less than 12 months, gross unrealized losses	(1,359)	(156)
Securities available for sale, 12 months or more, fair value	2,482	3,035
Securities available for sale, 12 months or more, gross unrealized losses	(639)	(140)
Securities available for sale, fair value	19,056	12,837
Securities available for sale, gross unrealized losses	(1,998)	(296)
Residential mortgage-backed and related securities
Securities available for sale:
Securities available for sale, less than 12 months, fair value	59,731	5,363
Securities available for sale, less than 12 months, gross unrealized losses	(2,073)	(67)
Securities available for sale, 12 months or more, fair value	18,215	19,406
Securities available for sale, 12 months or more, gross unrealized losses	(2,722)	(713)
Securities available for sale, fair value	77,946	24,769
Securities available for sale, gross unrealized losses	(4,795)	(780)
Asset-backed securities
Securities available for sale:
Securities available for sale, less than 12 months, fair value	10,722
Securities available for sale, less than 12 months, gross unrealized losses	(212)
Securities available for sale, fair value	10,722
Securities available for sale, gross unrealized losses	(212)
Other Securities
Securities available for sale:
Securities available for sale, less than 12 months, fair value	32,950	4,528
Securities available for sale, less than 12 months, gross unrealized losses	(1,084)	(30)
Securities available for sale, fair value	32,950	4,528
Securities available for sale, gross unrealized losses	$ (1,084)	$ (30)

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