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Statement of Accounting Policies - Additional Information (Detail) (USD $) | 12 Months Ended |
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Dec. 31, 2014 Segment | Dec. 31, 2013
Summary Of Significant Accounting Policies [Line Items] |  |
Business segments | 1us-gaap_NumberOfOperatingSegments |
Equity investments | 20.00%fcf_PercentageOfOwnershipInEquityInvestments |
Loans past due days | 90 days |
Excess impaired credits | $ 100,000fcf_ExcessImpairedLoanCredit |
Software purchases and developed are capitalized and amortized on straight-line basis | 7 years |
Future death benefit [Member] |  |
Summary Of Significant Accounting Policies [Line Items] |  |
Other liabilities | $ 3,900,000us-gaap_LiabilityForFuturePolicyBenefits / us-gaap_LongDurationContractsAssumptionsByProductAndGuaranteeGuaranteeTypeAxis = us-gaap_GuaranteedMinimumDeathBenefitMember | $ 3,600,000us-gaap_LiabilityForFuturePolicyBenefits / us-gaap_LongDurationContractsAssumptionsByProductAndGuaranteeGuaranteeTypeAxis = us-gaap_GuaranteedMinimumDeathBenefitMember

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- Definition Dollar threshold in which impaired credits are individually evaluated and reviewed. + References No definition available. + Details
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- Definition Loans Past Due Days + References No definition available. + Details
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- Definition Equity investments in which ownership is at least 20% are accounted for using the "equity method" of accounting and are classified as 'Other Assets". + References No definition available. + Details
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- Details
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- Definition Useful life of capitalized software amortized on a straight-line basis. + References No definition available. + Details
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- Definition Amount of accrued obligation to policyholders that relates to insured events for long-duration contracts. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 25 -Paragraph 11 -URI http://asc.fasb.org/extlink&oid=28366191&loc=d3e13145-158430 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 13 -Subparagraph a -Article 7 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03.13(a)(1)) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910 + Details
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- Definition Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues. + References No definition available. + Details
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- Details
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