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Note 12 - Minimum Regulatory Capital Requirement - Minimum Capital Requirements (Details) - USD ($) $ in Thousands | Dec. 31, 2016 | Dec. 31, 2015
--- | --- | ---
Total capital (to risk weighted assets), actual, amount | $ 191,006 |  | $ 184,054
Total capital (to risk weighted assets), actual, ratio | 26.575% |  | 25.527%
Total capital (to risk weighted assets), minimum capital requirement, amount | $ 57,499 | [1] | $ 57,681
Total capital (to risk weighted assets), minimum capital requirement, ratio | 8.625% | [1] | 8.00%
Total capital (to risk weighted assets), minimum to be well capitalized, amount |  |  |
Total capital (to risk weighted assets), minimum to be well capitalized, ratio |  |  |
Tier 1 capital (to risk weighted assets), actual, amount | $ 182,706 |  | $ 175,757
Tier 1 capital (to risk weighted assets), actual, ratio | 25.42% |  | 24.376%
Tier 1 capital (to risk weighted assets), minimum capital requirement, amount | $ 43,124 | [1] | $ 43,261
Tier 1 capital (to risk weighted assets), minimum capital requirement, ratio | 6.625% | [1] | 6.00%
Tier 1 capital (to risk weighted assets), minimum to be well capitalized, amount |  |  |
Tier 1 capital (to risk weighted assets), minimum to be well capitalized, ratio |  |  |
Common equity tier 1 capital (to risk weighted assets), actual, amount | $ 182,706 |  | $ 175,757
Common equity tier 1 capital (to risk weighted assets), actual, ratio | 25.42% |  | 24.376%
Common equity tier 1 capital (to risk weighted assets), minimum capital requirement, amount | $ 32,343 | [1] | $ 32,446
Common equity tier 1 capital (to risk weighted assets), minimum capital requirement, ratio | 5.125% | [1] | 4.50%
Common equity tier 1 capital (to risk weighted assets), minimum to be well capitalized, amount |  |  |
Common equity tier 1 capital (to risk weighted assets), minimum to be well capitalized, ratio |  |  |
Tier 1 capital (to average assets), actual, amount | $ 182,706 |  | $ 175,757
Tier 1 capital (to average assets), actual, ratio | 15.121% |  | 15.088%
Tier 1 capital (to average assets), minimum capital requirement, amount | $ 48,333 | [1] | $ 46,594
Tier 1 capital (to average assets), minimum capital requirement, ratio | 4.00% | [1] | 4.00%
Tier 1 capital (to average assets), minimum to be well capitalized, amount |  |  |
Tier 1 capital (to average assets), minimum to be well capitalized, ratio |  |  |
National Bank of Blacksburg [Member] |  |  |
Total capital (to risk weighted assets), actual, amount | $ 188,095 |  | $ 181,926
Total capital (to risk weighted assets), actual, ratio | 26.296% |  | 25.30%
Total capital (to risk weighted assets), minimum capital requirement, amount | $ 57,224 | [1] | $ 57,526
Total capital (to risk weighted assets), minimum capital requirement, ratio | 8.625% | [1] | 8.00%
Total capital (to risk weighted assets), minimum to be well capitalized, amount | $ 71,529 |  | $ 71,908
Total capital (to risk weighted assets), minimum to be well capitalized, ratio | 10.00% |  | 10.00%
Tier 1 capital (to risk weighted assets), actual, amount | $ 179,795 |  | $ 173,629
Tier 1 capital (to risk weighted assets), actual, ratio | 25.136% |  | 24.146%
Tier 1 capital (to risk weighted assets), minimum capital requirement, amount | $ 42,918 | [1] | $ 43,145
Tier 1 capital (to risk weighted assets), minimum capital requirement, ratio | 6.625% | [1] | 6.00%
Tier 1 capital (to risk weighted assets), minimum to be well capitalized, amount | $ 57,224 |  | $ 57,526
Tier 1 capital (to risk weighted assets), minimum to be well capitalized, ratio | 8.00% |  | 8.00%
Common equity tier 1 capital (to risk weighted assets), actual, amount | $ 179,795 |  | $ 173,629
Common equity tier 1 capital (to risk weighted assets), actual, ratio | 25.136% |  | 24.146%
Common equity tier 1 capital (to risk weighted assets), minimum capital requirement, amount | $ 32,188 | [1] | $ 32,358
Common equity tier 1 capital (to risk weighted assets), minimum capital requirement, ratio | 5.125% | [1] | 4.50%
Common equity tier 1 capital (to risk weighted assets), minimum to be well capitalized, amount | $ 46,494 |  | $ 46,740
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 | $ 179,795 |  | $ 173,629
Tier 1 capital (to average assets), actual, ratio | 14.964% |  | 14.888%
Tier 1 capital (to average assets), minimum capital requirement, amount | $ 48,060 | [1] | $ 46,648
Tier 1 capital (to average assets), minimum capital requirement, ratio | 4.00% | [1] | 4.00%
Tier 1 capital (to average assets), minimum to be well capitalized, amount | $ 60,075 |  | $ 58,310
Tier 1 capital (to average assets), minimum to be well capitalized, ratio | 5.00% |  | 5.00%
[1] | Except with regard to the Company's and the Bank's Tier 1 capital to average assets ratio, the minimum capital requirement includes the current phased-in portion of the Basel III Capital Rules capital conservation buffer (0.625%) which is added to the minimum capital requirements for capital adequacy purposes. The capital conservation buffer is being phased in through four equal annual installments of 0.625% from 2016 to 2019, with full implementation in January 2019 (2.5%). The Company's and the Bank's capital conservation buffer must consist 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 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 amount of total capital as defined in the regulations. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 948 -SubTopic 10 -Section 50 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=6490092&loc=d3e47304-110998 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1H -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=35709795&loc=d3e65071-112826 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1H -Subparagraph (c)(2) -URI http://asc.fasb.org/extlink&oid=35709795&loc=d3e65071-112826 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 948 -SubTopic 10 -Section 50 -Paragraph 3 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=6490092&loc=d3e47080-110998 + Details
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- Definition The minimum amount of Total Capital required for capital adequacy purposes under the regulatory framework for prompt corrective action. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1H -Subparagraph (c)(2) -URI http://asc.fasb.org/extlink&oid=35709795&loc=d3e65071-112826 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=35709795&loc=SL5958568-112826 + Details
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- Definition The minimum Total risk based capital ratio (total capital divided by risk weighted assets) required for capital adequacy purposes under the regulatory framework for prompt corrective action. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=35709795&loc=SL5958568-112826 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1H -Subparagraph (c)(2) -URI http://asc.fasb.org/extlink&oid=35709795&loc=d3e65071-112826 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1B -URI http://asc.fasb.org/extlink&oid=35709795&loc=SL5958570-112826 + Details
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- Definition The amount of Total Capital required to be categorized as well as capitalized under the regulatory framework for prompt corrective action. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=35709795&loc=SL5958568-112826 + Details
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- Definition Tier 1 Leverage Capital as defined in the regulations. Also called Core Capital. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=35709795&loc=SL5958568-112826 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1H -Subparagraph (c)(2) -URI http://asc.fasb.org/extlink&oid=35709795&loc=d3e65071-112826 + Details
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- Definition The minimum amount of Tier 1 Leverage Capital required for capital adequacy purposes under the regulatory framework for prompt corrective action. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1H -Subparagraph (c)(2) -URI http://asc.fasb.org/extlink&oid=35709795&loc=d3e65071-112826 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=35709795&loc=SL5958568-112826 + Details
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- Definition The minimum amount of Tier 1 Leverage Capital for capital adequacy purposes divided by average assets as defined in the regulations. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=35709795&loc=SL5958568-112826 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1H -Subparagraph (c)(2) -URI http://asc.fasb.org/extlink&oid=35709795&loc=d3e65071-112826 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1B -URI http://asc.fasb.org/extlink&oid=35709795&loc=SL5958570-112826 + Details
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- Definition The amount of Tier 1 Leverage Capital required to be categorized as well capitalized under the regulatory framework for prompt corrective action. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=35709795&loc=SL5958568-112826 + Details
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- Definition Tier 1 Risk Based Capital as defined in the regulations. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=35709795&loc=SL5958568-112826 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1H -Subparagraph (c)(2) -URI http://asc.fasb.org/extlink&oid=35709795&loc=d3e65071-112826 + Details
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- Definition The minimum amount of Tier 1 Risk Based Capital required for capital adequacy purposes under the regulatory framework for prompt corrective action. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1H -Subparagraph (c)(2) -URI http://asc.fasb.org/extlink&oid=35709795&loc=d3e65071-112826 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=35709795&loc=SL5958568-112826 + Details
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- Definition The minimum Tier One Capital Ratio (Tier one capital divided by risk-weighted assets) required for capital adequacy purposes under the regulatory framework for prompt corrective action. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=35709795&loc=SL5958568-112826 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1B -URI http://asc.fasb.org/extlink&oid=35709795&loc=SL5958570-112826 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1H -Subparagraph (c)(2) -URI http://asc.fasb.org/extlink&oid=35709795&loc=d3e65071-112826 + Details
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- Definition The amount of Tier 1 Risk Based Capital required to be categorized as well capitalized under the regulatory framework for prompt corrective action. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=35709795&loc=SL5958568-112826 + Details
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- Definition The Tier 1 capital ratio (Tier 1 capital divided by risk weighted assets) required to be categorized as "well capitalized" under the regulatory framework for prompt corrective action. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=35709795&loc=SL5958568-112826 + Details
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