| **Earnings Per Share**            | 3 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          |
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| **Earnings Per Share [Abstract]** |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    |
| Earnings Per Share                | Earnings Per ShareBasic net earnings (loss) per share, or basic earnings (loss) per share (“EPS”), is computed by dividing net loss to common shareholders by the weighted average number of common shares outstanding for the period.  We retired our Series A preferred stock in 2011.Diluted EPS reflects the potential dilution that could occur if COB's potential common stock, which consists of dilutive stock options and a common stock warrant, were issued.  As required for entities with complex capital structures, a dual presentation of basic and diluted EPS is included on the face of the income statement, and a reconciliation of the numerator and denominator of the basic EPS computation to the numerator and denominator of the diluted EPS computation is provided in this note.(dollars in thousands, except per share data) For Three Months Ended  March 31, 2014 March 31, 2013Net income (loss) $1,277 $(4,596)Weighted average number of shares outstanding - basic and diluted 21,935,566 21,698,115Net income (loss) per share - basic and diluted $0.06 $(0.21)During the three months ended March 31, 2014 and 2013, the price of the Company's common stock (as quoted on the Nasdaq Capital Market) was below the exercise price of all vested stock options and the common stock warrant. As a result, the options and warrants were considered antidilutive and thus are not included in the diluted share calculation.  For the three months ended March 31, 2014, there were 22,742 antidilutive shares. For the three months ended March 31, 2013, there were 23,123 antidilutive shares. Of the antidilutive shares, the number of shares relating to stock options were 670 for the three months ended March 31, 2014, and 1,051 for the three months ended March 31, 2013, while the number relating to the warrant was 22,072 for all periods presented. |

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| - Definition
The entire disclosure for earnings per share.
+ References
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