Note 4 - Loans - Changes in the Allowance, Off-balance-sheet Commitments (Details) - SEC Schedule, 12-09, Reserve, Off-balance Sheet Activity [Member] - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Balance	$ 396	$ 305
Provision charged to operations for off balance sheet	31	91
Balance	$ 427	$ 396

Amount of increase (decrease) in valuation and qualifying accounts and reserves.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 4
-Subparagraph (SX 210.12-09)
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e24092-122690

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