Note 15 - Fair Values of Financial Instruments - Notional Amount of Off-Balance Sheet Commitment Financial Instruments (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017
Fixed rate	$ 16,971	$ 17,063
Variable rate	88,711	72,667
Commitments to Extend Credit [Member]
Fixed rate	684	8,611
Variable rate	7,450	1,022
Unused lines of Credit [Member]
Fixed rate	16,287	8,452
Variable rate	$ 81,261	$ 71,645

Reflects the amount of cash required to fully fund agreements to provide advances to borrowers and lessees at interest rates that increase or decrease depending on certain facts or circumstances.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 825
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=108315417&loc=d3e61082-112788

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 825
-Section 50
-Paragraph 1
-Subparagraph (b)(2)
-URI http://asc.fasb.org/extlink&oid=108315417&loc=d3e61044-112788

Name:	us-gaap_LoansAndLeasesReceivableCommitmentsVariableRates
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration