Note 3 - Securities - Amortized Cost and Fair Value of Securities By Contractual Maturity (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Due in one year or less, amortized cost	$ 32,576
Due in one year or less, fair value	32,577
Due after one year through five years, amortized cost	651
Due after one year through five years, fair value	659
Amortized cost, single maturity date	33,227
Fair value, single maturity date	33,236
Amortized cost	41,732	$ 59,884
Fair value	42,048	60,193
Residential Mortgage Backed Securities [Member]
Amortized cost, without single maturity date	6,124
Fair value, without single maturity date	6,429
Amortized cost	6,124	7,727
Fair value	6,429	8,037
Collateralized Mortgage Backed Securities [Member]
Amortized cost, without single maturity date	2,381
Fair value, without single maturity date	2,383
Amortized cost	2,381	2,986
Fair value	$ 2,383	$ 2,977

Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section 50
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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