Note 21 - Regulatory Matters (Details Textual) $ in Thousands	Jun. 30, 2024 USD ($)	Dec. 31, 2023 USD ($)	Mar. 07, 2022
Banking Regulation, Capital Conservation Buffer, Capital Conserved, Minimum	0.025
Common Equity Tier One Risk Based Capital, Required to Be Well Capitalized to Risk Weighted Assets Including Capital Conservation Buffer	7.00%
Tier One Risk Based Capital Required for Capital Adequacy to Risk Weighted Assets Including Capital Conservation Buffer	8.50%
Capital Required for Capital Adequacy to Risk Weighted Assets Including Capital Conservation Buffer	10.50%
Subordinated Debt	$ 26,806	$ 26,740
Commonwealth [Member]
Business Acquisition, Percentage of Voting Interests Acquired			100.00%
Subordinated Debt	$ 26,000
Commonwealth [Member] \| Commonwealth Statutory Trust III [Member]
Business Acquisition, Percentage of Voting Interests Acquired			100.00%
Commonwealth [Member] \| Commonwealth Statutory Trust IV [Member]
Business Combination, Unconsolidated Trust Subsidiaries Acquired, Percent			100.00%
Commonwealth [Member] \| Commonwealth Statutory Trust V [Member]
Business Combination, Unconsolidated Trust Subsidiaries Acquired, Percent			100.00%
Subsidiaries [Member]
Banking Regulation, Common Equity Tier 1 Risk-Based Capital Ratio, Well Capitalized, Minimum	0.065	0.065
Banking Regulation, Tier 1 Risk-Based Capital Ratio, Well Capitalized, Minimum	0.08	0.08
Banking Regulation, Total Risk-Based Capital Ratio, Well Capitalized, Minimum	0.10	0.10
Banking Regulation, Tier 1 Leverage Capital Ratio, Well Capitalized, Minimum	0.05	0.05

The percent of unconsolidated trust subsidiaries acquired under business combination.

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- Definition

Represents capital required for capital adequacy to risk weighted assets including capital conservation buffer.

+ References

No definition available.

+ Details

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- Definition

The Common Equity Tier 1 capital ratio required to be categorized as "well capitalized" under the regulatory framework for prompt corrective action.

+ References

No definition available.

+ Details

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- Definition

Represents tier one risk based capital required for capital adequacy to risk weighted assets including capital conservation buffer.

+ References

No definition available.

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- Definition

Minimum capital conservation buffer percentage required to avoid restriction on payout amount of eligible retained income 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

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- Definition

Ratio of minimum Common Equity Tier 1 risk-based capital to risk-weighted assets categorized as well capitalized as defined by regulatory framework for prompt corrective action.

+ References

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- Definition

Percentage of voting equity interests acquired at the acquisition date in the business combination.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479328/805-10-50-2

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- Definition

Ratio of minimum total risk-based capital to risk-weighted assets categorized as well capitalized as defined by regulatory framework for prompt corrective action.

+ References

+ Details

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- Definition

Including the current and noncurrent portions, carrying value as of the balance sheet date of subordinated debt (with initial maturities beyond one year or beyond the operating cycle if longer). Subordinated debt places a lender in a lien position behind debt having a higher priority of repayment in liquidation of the entity's assets.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-SubTopic 10
-Topic 210
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(19))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 942
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478546/942-210-S99-1

Reference 4: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 944
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(16)(a)(2))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478777/944-210-S99-1

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- Definition

Ratio of minimum Tier 1 leverage capital to average assets categorized as well capitalized as defined by regulatory framework for prompt corrective action.

+ References

+ Details

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- Definition

Ratio of minimum Tier 1 risk-based capital to risk-weighted assets categorized as well capitalized as defined by regulatory framework for prompt corrective action.

+ References

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