Note 3 - Debt Securities - Available For Sale Securities in Continuous Unrealized Loss Position (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Securities available for sale, less than 12 months, fair value	$ 0	$ 8,995
Securities available for sale, less than 12 months, unrealized losses	0	(52)
Securities available for sale, 12 months or longer, fair value	586	8,319
Securities available for sale, 12 months or longer, unrealized losses	(4)	(118)
Securities available for sale, total fair value	586	17,314
Securities available for sale, total unrealized losses	(4)	(170)
US Government Agencies Debt Securities [Member]
Securities available for sale, less than 12 months, fair value	0	975
Securities available for sale, less than 12 months, unrealized losses	0	(4)
Securities available for sale, 12 months or longer, fair value	586	0
Securities available for sale, 12 months or longer, unrealized losses	(4)	0
Securities available for sale, total fair value	586	975
Securities available for sale, total unrealized losses	(4)	(4)
Mortgage-backed Agency Securities [Member]
Securities available for sale, less than 12 months, fair value	0	8,020
Securities available for sale, less than 12 months, unrealized losses	0	(48)
Securities available for sale, 12 months or longer, fair value	0	8,319
Securities available for sale, 12 months or longer, unrealized losses	0	(118)
Securities available for sale, total fair value	0	16,339
Securities available for sale, total unrealized losses	$ 0	$ (166)

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.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 30
-Section 50
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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Amount of accumulated unrealized loss on 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 12 months or longer, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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