| **Commitments and Contingent Liabilities**              | 6 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               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| **Commitments and Contingencies Disclosure [Abstract]** |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    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| Commitments and Contingent Liabilities                  | Commitments and Contingent LiabilitiesCommitments and letters of creditStandby letters of credit and commercial letters of credit are conditional commitments issued by First Commonwealth to guarantee the performance of a customer to a third party. The contract or notional amount of these instruments reflects the maximum amount of future payments that First Commonwealth could be required to pay under the guarantees if there were a total default by the guaranteed parties, without consideration of possible recoveries under recourse provisions or from collateral held or pledged. In addition, many of these commitments are expected to expire without being drawn upon; therefore, the total commitment amounts do not necessarily represent future cash requirements.The following table identifies the notional amount of those instruments at: June 30, 2014 December 31, 2013 (dollars in thousands)Financial instruments whose contract amounts represent credit risk:   Commitments to extend credit$1,532,655 $1,571,987Financial standby letters of credit36,533 38,121Performance standby letters of credit27,178 32,441Commercial letters of credit— — The notional amounts outstanding as of June 30, 2014 include amounts issued in 2014 of $0.3 million in financial standby letters of credit and $0.5 million in performance standby letters of credit. There were no commercial letters of credit issued during 2014. A liability of $0.1 million has been recorded as of June 30, 2014 and December 31, 2013, which represents the estimated fair value of letters of credit issued. The fair value of letters of credit is estimated based on the unrecognized portion of fees received at the time the commitment was issued.Unused commitments and letters of credit provide exposure to future credit loss in the event of nonperformance by the borrower or guaranteed parties. Management’s evaluation of the credit risk related to these commitments resulted in the recording of a liability of $3.1 million as of June 30, 2014 and $3.2 million as of December 31, 2013. The credit risk evaluation incorporated probability of default, loss given default and estimated utilization for the next twelve months for each loan category and the letters of credit.Legal proceedingsMarket Rate Savings IRA LitigationMcGrogan v. First Commonwealth Bank was filed as a class action on January 12, 2009, in the Court of Common Pleas of Allegheny County, Pennsylvania. The action alleges that First Commonwealth Bank (the “Bank”) promised class members a minimum interest rate of 8% on its IRA Market Rate Savings Account for as long as the class members kept their money on deposit in the IRA account. The class asserted that the Bank committed fraud, breached its modified contract with the class members, and violated the Pennsylvania Unfair Trade Practice and Consumer Protection Law (UTPCPL) when it resigned as custodian of the IRA Market Rate Savings Accounts in 2008 and offered the class members a roll-over IRA account with a 3.5% interest rate. Plaintiffs sought monetary damages for the alleged breach of contract, punitive damages for the alleged fraud and Unfair Trade Practice and Consumer Protection Law violations and attorney’s fees.  The court granted class certification as to the breach of modified contract claim and denied class certification as to the fraud and Pennsylvania Unfair Trade Practice and Consumer Protection Law claims. The breach of contract claim was predicated upon a letter sent to customers in 1998 which reversed an earlier decision by the Bank to reduce the rate paid on the accounts. The letter stated, in relevant part, “This letter will serve as notification that a decision has been made to re-establish the rate on your account to eight percent (8)%. This rate will be retroactive to your most recent maturity date and will continue going forward on deposits presently in the account and on annual additions.” On August 30, 2012, the Court entered an order granting the Bank’s motion for summary judgment and dismissed the class action claims. The Court found that the Bank retained the right to resign as custodian of the accounts and that the act of resigning as custodian and closing the accounts did not breach the terms of the underlying IRA contract. On appeal, the Superior Court affirmed the denial of class certification to the claims of fraud in the execution and violation of the UTPCPL.  The Superior Court found that none of the other issues were ripe for appeal.  Jurisdiction was returned to the Court of Common Pleas where the individual fraud and UTPCPL claims of Mr. and Mrs. McGrogan are pending.  Plaintiffs filed their pretrial statement on June 16, 2014, seeking $0.5 million in damages for the McGrogans and $0.8 million for their adult children beneficiaries.  The Bank considers these damage claims exaggerated and otherwise invalid.  The Bank has filed a motion for summary judgment; it is pending.In December 2013, three new complaints were filed by 34 former members of the McGrogan class:(1)Jarrett et al. v. First Commonwealth Bank - An action filed by eight plaintiffs on December 2, 2013 in the Westmoreland County Court of Common Pleas asserting claims for fraud in the inducement, fraud in the execution, violation of the UTPCPL, breach of fiduciary duty and promissory estoppel.(2)Young et al. v. First Commonwealth Bank - An action filed by 12 plaintiffs on December 2, 2013 in the Westmoreland County Court of Common Pleas asserting claims for fraud in the inducement, fraud in the execution, violation of the UTPCPL, breach of fiduciary duty and promissory estoppel.(3)Fisanik et. al. v. First Commonwealth Bank - An action filed by 14 plaintiffs on December 9, 2013 in the Cambria County Court of Common Pleas asserting claims for fraud in the inducement, fraud in the execution, violation of the UTPCPL, and breach of fiduciary duty.The 36 plaintiffs who have filed individual actions held Market Rate Savings IRA balances totaling approximately $4 million at the time of the Bank’s resignation as custodian of the IRAs in 2008.  The average age of the plaintiffs at that time was 62.  The Bank filed preliminary objections to the three new complaints.  On July 22, 2014 the court issued an order permitting the three new cases to proceed only on theories of fraud in the execution and violation of the UTPCPL based on fraud in the execution and dismissing the claims for fraud in the inducement, breach of fiduciary duty and promissory estoppel with prejudice.At this time, the Bank believes the claims are without merit.Other mattersIn 2013, First Commonwealth identified an error related to historical tax reporting for approximately 700-900 customers, resulting in the establishment of an $0.8 million contingency reserve. During the second quarter of 2014,  a settlement in the amount of $0.4 million was reached with one taxing authority, while resolution with another taxing authority continues. Based on the settlement reached, management's best estimate of the remaining liability for this issue is $0.1 million. As a result, in addition to the settlement amount,  $0.3 million of the contingency reserve was reversed during the second quarter of 2014. The contingency reserve is included in “Other liabilities” in the Condensed Consolidated Statements of Financial Condition.  There are no other material legal proceedings to which First Commonwealth or its subsidiaries are a party, or of which their property is the subject, except proceedings which arise in the normal course of business and, in the opinion of management, will not have a material adverse effect on the consolidated operations, financial position or cash flow of First Commonwealth or its subsidiaries. |

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| - Definition
The entire disclosure for commitments, contingencies, and guarantees.
+ References
No definition available.
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