Note 12 - Regulatory Capital Requirements (Details Textual)	Dec. 31, 2025	Dec. 31, 2024	Jan. 01, 2019	Jan. 01, 2015
Banking Regulation, Common Equity Tier One Risk-Based Capital Ratio, Capital Adequacy, Minimum	0.045	0.045		0.045
Banking Regulation, Tier One Risk-Based Capital Ratio, Capital Adequacy, Minimum	0.06	0.06		0.06
Banking Regulation, Total Risk-Based Capital Ratio, Capital Adequacy, Minimum	0.08	0.08		0.08
Banking Regulation, Tier One Leverage Capital Ratio, Capital Adequacy, Minimum	0.04	0.04		0.04
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
-Topic 942
-SubTopic 505
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (c)(1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477270/942-505-50-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 942
-SubTopic 505
-Name Accounting Standards Codification
-Section 50
-Paragraph 1B
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477270/942-505-50-1B

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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

+ Details

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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

+ Details

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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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