| **Subsequent Event**             | 12 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      |
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| **Subsequent Events [Abstract]** |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 |
| Subsequent Event                 | Subsequent EventOn January 28, 2014, an additional share repurchase program was authorized for up to $25.0 million in shares of the Company’s common stock. Under this program, management is authorized to repurchase shares through Rule 10b5-1 plans, open market purchases, privately negotiated transactions, block purchases or otherwise in accordance with applicable federal securities laws, including Rule 10b-18 of the Securities Exchange Act of 1934.  Depending on market conditions and other factors, repurchases may be made at any time or from time to time, without prior notice. First Commonwealth may suspend or discontinue the program at any time. |

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| - Definition
The entire disclosure for significant events or transactions that occurred after the balance sheet date through the date the financial statements were issued or the date the financial statements were available to be issued. Examples include: the sale of a capital stock issue, purchase of a business, settlement of litigation, catastrophic loss, significant foreign exchange rate changes, loans to insiders or affiliates, and transactions not in the ordinary course of business.
+ References
No definition available.
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