| **Capital Matters (Tables)**                    | 12 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            |
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| **Capital Matters [Abstract]**                  |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |
| Compliance with Regulatory Capital Requirements | Quantitative measures established by regulation to ensure capital adequacy require each bank to maintain minimum amounts and ratios (set forth in the accompanying table) of total and Tier 1 capital (as defined in the regulations) to risk-weighted assets (as defined), and of Tier 1 capital to average assets (as defined).       Minimum Regulatory Requirement to be Well Capitalized(dollars in thousands) Actual For CapitalAdequacy Purposes Under PromptCorrective ActionProvisions Pursuantto Order  Amount Ratio Amount Ratio Amount Ratio RatioDecember 31, 2012                  Total Capital (to Risk Weighted Assets)                  Consolidated $158,993 12.34% $103,051   8.00% N/A      CommunityOne Bank, N.A. 103,976 11.40 72,997   8.00 $91,247   10.00% 12.00%Bank of Granite 60,896 16.30 29,893   8.00 37,366   10.00 12.00Tier 1 Capital (to Risk Weighted Assets)                  Consolidated 119,242 9.26 $51,525   — N/A      CommunityOne Bank, N.A. 92,418 10.13 36,499   4.00 $54,748   6.00% 9.00%Bank of Granite 56,209 15.04 14,946   4.00 22,420   6.00 8.00Tier 1 Capital (to Average Assets)                  Consolidated 119,242 5.45 $87,567   — N/A      CommunityOne Bank, N.A. 92,418 6.17 59,909   4.00 $74,886   5.00% 9.00%Bank of Granite 56,209 8.12 27,675   4.00 34,594   5.00 8.00                   December 31, 2011                  Total Capital (to Risk Weighted Assets)                  Consolidated $193,725 13.81% $112,245   N/A N/A      CommunityOne Bank, N.A. 136,761 14.52 75,363   8.00 $94,204   10.00% 12.00%Bank of Granite 54,647 12.04 36,305   8.00 45,382   10.00 12.00Tier 1 Capital (to Risk Weighted Assets)                  Consolidated 164,253 11.71 56,123   N/A N/A      CommunityOne Bank, N.A. 124,639 13.23 37,682   4.00 $56,522   6.00% 9.00%Bank of Granite 54,633 12.04 18,153   4.00 27,229   6.00 8.00Tier 1 Capital (to Average Assets)                  Consolidated 164,253 6.70 98,092   N/A N/A      CommunityOne Bank, N.A. 124,639 7.39 67,426   4.00 $84,282   5.00% 9.00%Bank of Granite 54,633 7.19 30,410   4.00 38,013   5.00 8.00 |

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| - Definition
Tabular disclosure of the capital amounts and ratios as of the balance sheet date, indicating whether the entity or entities are in compliance with regulatory capital requirements, by entity.
+ References
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