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Note 11 - Minimum Regulatory Capital Requirement - Minimum Capital Requirements (Details) - National Bank of Blacksburg [Member] $ in Thousands | Dec. 31, 2021 USD ($) | Dec. 31, 2020 USD ($)
--- | --- | ---
Total capital (to risk weighted assets), actual, amount |  | $ 192,907 | $ 185,937
Total capital (to risk weighted assets), actual, ratio |  | 0.19495 | 0.19943
Total capital (to risk weighted assets), minimum capital requirement, amount | [1] | $ 103,898 | $ 97,898
Total capital (to risk weighted assets), minimum capital requirement, ratio | [1] | 0.10500 | 0.10500
Total capital (to risk weighted assets), minimum to be well capitalized, amount |  | $ 98,950 | $ 93,236
Total capital (to risk weighted assets), minimum to be well capitalized, ratio |  | 0.10000 | 0.10000
Tier 1 capital (to risk weighted assets), actual, amount |  | $ 185,187 | $ 177,409
Tier 1 capital (to risk weighted assets), actual, ratio |  | 0.18715 | 0.19028
Tier 1 capital (to risk weighted assets), minimum capital requirement, amount | [1] | $ 84,108 | $ 79,251
Tier 1 capital (to risk weighted assets), minimum capital requirement, ratio | [1] | 0.08500 | 0.08500
Tier 1 capital (to risk weighted assets), minimum to be well capitalized, amount |  | $ 79,160 | $ 74,589
Tier 1 capital (to risk weighted assets), minimum to be well capitalized, ratio |  | 0.08000 | 0.08000
Common equity tier 1 capital (to risk weighted assets), actual, amount |  | $ 185,187 | $ 177,409
Common equity tier 1 capital (to risk weighted assets), actual, ratio |  | 0.18715 | 0.19028
Common equity tier 1 capital (to risk weighted assets), minimum capital requirement, amount | [1] | $ 69,265 | $ 65,265
Common equity tier 1 capital (to risk weighted assets), minimum capital requirement, ratio | [1] | 7.00% | 7.00%
Common equity tier 1 capital (to risk weighted assets), minimum to be well capitalized, amount |  | $ 64,318 | $ 60,604
Common equity tier 1 capital (to risk weighted assets), minimum to be well capitalized, ratio |  | 6.50% | 6.50%
Tier 1 capital (to average assets), actual, amount |  | $ 185,187 | $ 177,409
Tier 1 capital (to average assets), actual, ratio |  | 0.11165 | 0.12105
Tier 1 capital (to average assets), minimum capital requirement, amount | [1] | $ 66,348 | $ 58,624
Tier 1 capital (to average assets), minimum capital requirement, ratio | [1] | 0.04000 | 0.04000
Tier 1 capital (to average assets), minimum to be well capitalized, amount |  | $ 82,935 | $ 73,281
Tier 1 capital (to average assets), minimum to be well capitalized, ratio |  | 0.05000 | 0.05000
[1] | Except with regard to NBB’s Tier 1 capital to average assets ratio, the minimum capital requirement includes the Basel III Capital Rules’ capital conservation buffer (2.50%) which is added to the minimum capital requirements for capital adequacy purposes. NBB’s capital conservation buffer consists of additional CET1 above regulatory minimum requirement. Failure to maintain the prescribed levels would result in limitations on capital distributions and discretionary bonuses to executives.

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- Definition Amount of minimum Tier 1 risk-based capital required for capital requirement as defined by regulatory framework. + References No definition available. + Details
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- Definition The minimum amount of common equity tier 1 capital required for capital adequacy purposes under the regulatory framework for prompt corrective action. + References No definition available. + Details
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- Definition The common equity tier 1 risk based capital ratio (common equity tier 1 capital divided by risk weighted assets) required to be categorized as "well capitalized", in the regulatory framework for prompt corrective action. + References No definition available. + Details
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- Definition Amount of total capital 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 1 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=117337116&loc=SL5958568-112826 + Details
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- Definition Amount of Common Equity Tier 1 risk-based capital 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 1 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=117337116&loc=SL5958568-112826 + Details
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