Note 11 - Regulatory Capital Requirements (Details Textual)	Dec. 31, 2021	Dec. 31, 2020	Jan. 01, 2019	Jan. 01, 2015
Banking Regulation, Common Equity Tier One Risk-Based Capital Ratio, Capital Adequacy, Minimum	0.0450	0.0450		0.045
Banking Regulation, Tier One Risk-Based Capital Ratio, Capital Adequacy, Minimum	0.0600	0.0600		0.060
Banking Regulation, Total Risk-Based Capital Ratio, Capital Adequacy, Minimum	0.0800	0.0800		0.080
Banking Regulation, Tier One Leverage Capital Ratio, Capital Adequacy, Minimum	0.0400	0.0400		0.040
Excess Tier One Common Equity, Capital Conservation Buffer			2.50%

The capital conservation buffer of excess tier one common equity.

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- Definition

Ratio of minimum Common Equity Tier 1 risk-based capital to risk-weighted assets required for capital adequacy as defined by regulatory framework.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 505
-Section 50
-Paragraph 1B
-URI http://asc.fasb.org/extlink&oid=117337116&loc=SL5958570-112826

Reference 2: 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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- Definition

Ratio of minimum total risk-based capital to risk-weighted assets required for capital adequacy as defined by regulatory framework.

+ References

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- Definition

Ratio of minimum Tier 1 leverage capital to average assets required for capital adequacy as defined by regulatory framework.

+ References

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- Definition

Ratio of minimum Tier 1 risk-based capital to risk-weighted assets required for capital adequacy as defined by regulatory framework.

+ References

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