| **Capital**                                              | 12 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 |
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| **Disclosure Capital Additional Information [Abstract]** |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            |
| Capital                                                  | CapitalOn June 19, 2012 First Commonwealth announced a $50.0 million  common stock repurchase program. On January 29, 2013, an additional share repurchase program was authorized for up to $25.0 million in shares of the Company’s common stock.  On January 28, 2014, an additional share repurchase program was authorized for up to $25.0 million in shares of the Company's common stock.  As of December 31, 2014, all three programs were completed resulting in a total of 13,734,185 shares repurchased at an average price of $7.31 per share. |

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| - Definition
The entire disclosure for shareholders' equity comprised of portions attributable to the parent entity and noncontrolling interest, including other comprehensive income. Includes, but is not limited to, balances of common stock, preferred stock, additional paid-in capital, other capital and retained earnings, accumulated balance for each classification of other comprehensive income and amount of comprehensive income.
+ References
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