Note 2 - Securities - Securities in a Continuous Unrealized Loss Position (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Less than 12 months, fair value	$ 46,564	$ 31,421
12 months or more, fair value	16,477	50,394
12 months or more, unrealized loss	(218)	(1,570)
Total, fair value	63,041	81,815
Total, unrealized loss	(824)	(2,007)
Less than 12 months, unrealized loss	(606)	(437)
US Government Agencies Debt Securities [Member]
Less than 12 months, fair value		2,472
12 months or more, fair value	2,032	10,337
12 months or more, unrealized loss	(6)	(269)
Total, fair value	2,032	12,809
Total, unrealized loss	(6)	(299)
Less than 12 months, unrealized loss		(30)
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member]
Less than 12 months, fair value	14,578	19,483
12 months or more, fair value	2,325	7,693
12 months or more, unrealized loss	(8)	(193)
Total, fair value	16,903	27,176
Total, unrealized loss	(84)	(490)
Less than 12 months, unrealized loss	(76)	(297)
Collateralized Mortgage Obligations [Member]
Less than 12 months, fair value	12,319	1,443
12 months or more, fair value	11,621	15,388
12 months or more, unrealized loss	(203)	(805)
Total, fair value	23,940	16,831
Total, unrealized loss	(235)	(810)
Less than 12 months, unrealized loss	(32)	(5)
US States and Political Subdivisions Debt Securities [Member]
Less than 12 months, fair value	15,636	7,061
12 months or more, fair value		10,083
12 months or more, unrealized loss		(157)
Total, fair value	15,636	17,144
Total, unrealized loss	(269)	(224)
Less than 12 months, unrealized loss	(269)	(67)
Corporate Debt Securities [Member]
Less than 12 months, fair value	4,031	962
12 months or more, fair value	499	2,448
12 months or more, unrealized loss	(1)	(59)
Total, fair value	4,530	3,410
Total, unrealized loss	(230)	(97)
Less than 12 months, unrealized loss	$ (229)	(38)
US Treasury and Government [Member]
Less than 12 months, fair value
12 months or more, fair value		4,445
12 months or more, unrealized loss		(87)
Total, fair value		4,445
Total, unrealized loss		$ (87)

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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