| **Acquisition by Capital Bank Financial Corp.** | 3 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |
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| **Business Combinations [Abstract]**            |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 |
| Acquisition by Capital Bank Financial Corp.     | Acquisition by Capital Bank Financial Corp.On November 22, 2015, we entered into an Agreement and Plan of Merger (“Merger Agreement”) with Capital Bank Financial Corp., a Delaware corporation (“Capital”), under which, upon the terms and subject to the conditions set forth in the Merger Agreement, COB will merge with and into Capital (the “Merger”), with Capital as the surviving corporation in the Merger.  Immediately following the Merger, the Bank will merge with and into Capital’s wholly-owned bank subsidiary, with Capital’s wholly-owned bank subsidiary surviving the bank merger.  Shareholders of both COB and Capital approved the Merger on April 18, 2016.  The Merger is subject to, among other things, regulatory approval and other customary closing conditions and is currently expected to close in the second quarter of 2016. |

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| - Definition
The entire disclosure for a business combination (or series of individually immaterial business combinations) completed during the period, including background, timing, and recognized assets and liabilities. The disclosure may include leverage buyout transactions (as applicable).
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No definition available.
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