| **Subordinated Debentures (Tables)**              | 12 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     |
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| **Disclosure Subordinated Debentures [Abstract]** |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                |
| Subordinated Debentures Outstanding               | Subordinated Debentures outstanding at December 31 are as follows:   2013 2012 Due Amount Rate Amount Rate   (dollars in thousands)Owed to:         First Commonwealth Capital Trust I2029 $—   $33,583 9.50%First Commonwealth Capital Trust II2034 30,929 LIBOR + 2.85 30,929 LIBOR + 2.85First Commonwealth Capital Trust III2034 41,238 LIBOR + 2.85 41,238 LIBOR + 2.85Total  $72,167   $105,750   |

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| - Definition
Tabular disclosure of borrowings under subordinated debt agreements that qualify as available in computing net capital under SEC uniform net capital rules for broker-dealers, including restrictive covenants, collateral, interest rates and due dates, amounts due by date and amount owed in total.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Audit and Accounting Guide (AAG) -Number AAG-BRD -Paragraph 80 -Subparagraph Exhibit 4-8 -IssueDate 2006-05-01 -Chapter 4 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.  This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Audit and Accounting Guide (AAG) -Number AAG-BRD -Paragraph 80 -Subparagraph Exhibit 4-8, 9 -IssueDate 2006-05-01 -Chapter 4 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.  This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.
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