Note 14 - Regulatory Capital Matters (Details Textual)	Mar. 31, 2020
Banking Regulation, Capital Conservation Buffer, Capital Conserved, Minimum	2.5
Banking Regulation, Capital Conservation Buffer, Common Equity Tier One Risk-Based Capital, Actual	7
Banking Regulation, Capital Conservation Buffer, Tier One Risk-Based Capital, Actual	8.5
Banking Regulation, Capital Conservation Buffer, Tier One Risk-Based Capital, Actual	10.5

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 http://asc.fasb.org/extlink&oid=117337116&loc=SL5958568-112826

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Capital conservation buffer percentage calculated as Common Equity Tier 1 risk-based capital ratio after deduction of minimum Common Equity Tier 1 risk-based capital ratio as defined by regulatory framework.

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Capital conservation buffer percentage calculated as Tier 1 risk-based capital ratio after deduction of minimum Tier 1 risk-based capital ratio as defined by regulatory framework.

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Capital conservation buffer percentage calculated as total risk-based capital ratio after deduction of minimum total risk-based capital ratio as defined by regulatory framework.

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