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Note 11 - Minimum Regulatory Capital Requirement (Details Textual) - USD ($) $ in Thousands | Dec. 31, 2025 | Dec. 31, 2024
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National Bank of Blacksburg [Member] |  |
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items] |  |
Banking Regulation, Risk-Weighted Assets, Actual | $ 1,188,194 | $ 1,232,207

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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -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 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -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 + Details
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- Definition Amount of risk-weighted assets 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 + Details
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