Note 8 - Regulatory Matters (Details Textual)	Dec. 31, 2019	Dec. 31, 2015
Banking Regulation, Capital Conservation Buffer, Capital Conserved, Minimum	0.0250	0.000

Minimum capital conservation buffer percentage required to avoid restriction on payout amount of eligible retained income as defined by regulatory framework.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 505
-Section 50
-Paragraph 1
-Subparagraph (c)(1)
-URI https://asc.fasb.org/extlink&oid=117337116&loc=SL5958568-112826

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Data Type:	xbrli:pureItemType
Balance Type:	na
Period Type:	instant