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Note 20 - Subsequent Event (Details Textual) - Subsequent Event [Member] $ / shares in Units, Pure in Millions, $ in Millions | Oct. 20, 2025 USD ($) $ / shares
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Share Price (in dollars per share) | $ 13.91
Middlefield Banc Corp [Member] |
Business Acquisition, Equity Conversion Ratio | 2.6
Business Combination, Price of Acquisition, Expected | $ | $ 299
Business Combination, Price Per Share (in dollars per share) | $ 36.17

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- Definition Per share price of saleable stock paid or offered to be paid by acquirer in business combination. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 805 -SubTopic 40 -Name Accounting Standards Codification -Section 55 -Paragraph 10 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479299/805-40-55-10 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 805 -SubTopic 30 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479581/805-30-50-2 Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 805 -SubTopic 30 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (b)(4) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479581/805-30-50-1 Reference 4: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 805 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 8 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479328/805-10-50-8 Reference 5: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 805 -SubTopic 10 -Name Accounting Standards Codification -Section 55 -Paragraph 42 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479303/805-10-55-42 + Details
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- Definition Purchase price of expected business acquisition prior to consideration being transferred. Excludes asset acquisition. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 805 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 7 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479328/805-10-50-7 + Details
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