XML 24 R50.htm IDEA: XBRL DOCUMENT
v3.3.0.814

Impairment of Investment Securities - Pooled Trust Preferred Collateralized Debt Obligations (Detail) $ in Thousands | 9 Months Ended |
--- | --- | ---
Sep. 30, 2015 USD ($) Bank | Dec. 31, 2014 USD ($)
Impairment Of Investment Securities [Line Items] |  |
Securities available for sale, at fair value | $ 1,050,733 | $ 1,309,819
Unrealized Gain (Loss) | 12,186 | $ 24,420
Pooled Trust Preferred Collateralized Debt Obligations [Member] |  |
Impairment Of Investment Securities [Line Items] |  |
Book Value | 42,000 |
Securities available for sale, at fair value | 35,779 |
Unrealized Gain (Loss) | (6,221) |
Pooled Trust Preferred Collateralized Debt Obligations [Member] | Mezzanine [Member] | Pre TSL IV [Member] |  |
Impairment Of Investment Securities [Line Items] |  |
Book Value | 1,830 |
Securities available for sale, at fair value | 1,337 |
Unrealized Gain (Loss) | $ (493) |
Debt Instrument, Credit Rating | B1/BB |
Number of Banks (in banks) | Bank | 6 |
Deferrals and Defaults as a % of Current Collateral | 18.05% |
Excess Subordination as a % of Current Performing Collateral | 57.96% |
Pooled Trust Preferred Collateralized Debt Obligations [Member] | Mezzanine [Member] | Pre TSL VII [Member] |  |
Impairment Of Investment Securities [Line Items] |  |
Book Value | $ 2,905 |
Securities available for sale, at fair value | 3,494 |
Unrealized Gain (Loss) | $ 589 |
Debt Instrument, Credit Rating | Ca/- |
Number of Banks (in banks) | Bank | 14 |
Deferrals and Defaults as a % of Current Collateral | 49.68% |
Excess Subordination as a % of Current Performing Collateral | 0.00% |
Pooled Trust Preferred Collateralized Debt Obligations [Member] | Mezzanine [Member] | Pre TSL VIII [Member] |  |
Impairment Of Investment Securities [Line Items] |  |
Book Value | $ 2,000 |
Securities available for sale, at fair value | 1,865 |
Unrealized Gain (Loss) | $ (135) |
Debt Instrument, Credit Rating | C/C |
Number of Banks (in banks) | Bank | 29 |
Deferrals and Defaults as a % of Current Collateral | 56.74% |
Excess Subordination as a % of Current Performing Collateral | 0.00% |
Pooled Trust Preferred Collateralized Debt Obligations [Member] | Mezzanine [Member] | Pre TSL IX [Member] |  |
Impairment Of Investment Securities [Line Items] |  |
Book Value | $ 2,367 |
Securities available for sale, at fair value | 1,811 |
Unrealized Gain (Loss) | $ (556) |
Debt Instrument, Credit Rating | B1/C |
Number of Banks (in banks) | Bank | 38 |
Deferrals and Defaults as a % of Current Collateral | 29.80% |
Excess Subordination as a % of Current Performing Collateral | 10.04% |
Pooled Trust Preferred Collateralized Debt Obligations [Member] | Mezzanine [Member] | Pre TSL X [Member] |  |
Impairment Of Investment Securities [Line Items] |  |
Book Value | $ 1,583 |
Securities available for sale, at fair value | 1,921 |
Unrealized Gain (Loss) | $ 338 |
Debt Instrument, Credit Rating | Caa1/C |
Number of Banks (in banks) | Bank | 43 |
Deferrals and Defaults as a % of Current Collateral | 30.66% |
Excess Subordination as a % of Current Performing Collateral | 0.00% |
Pooled Trust Preferred Collateralized Debt Obligations [Member] | Mezzanine [Member] | Pre TSL XII [Member] |  |
Impairment Of Investment Securities [Line Items] |  |
Book Value | $ 5,643 |
Securities available for sale, at fair value | 4,598 |
Unrealized Gain (Loss) | $ (1,045) |
Debt Instrument, Credit Rating | B3/C |
Number of Banks (in banks) | Bank | 66 |
Deferrals and Defaults as a % of Current Collateral | 23.07% |
Excess Subordination as a % of Current Performing Collateral | 0.00% |
Pooled Trust Preferred Collateralized Debt Obligations [Member] | Mezzanine [Member] | Pre TSL XIII [Member] |  |
Impairment Of Investment Securities [Line Items] |  |
Book Value | $ 12,646 |
Securities available for sale, at fair value | 10,704 |
Unrealized Gain (Loss) | $ (1,942) |
Debt Instrument, Credit Rating | B3/C |
Number of Banks (in banks) | Bank | 56 |
Deferrals and Defaults as a % of Current Collateral | 12.05% |
Excess Subordination as a % of Current Performing Collateral | 26.32% |
Pooled Trust Preferred Collateralized Debt Obligations [Member] | Mezzanine [Member] | Pre TSL XIV [Member] |  |
Impairment Of Investment Securities [Line Items] |  |
Book Value | $ 12,818 |
Securities available for sale, at fair value | 9,752 |
Unrealized Gain (Loss) | $ (3,066) |
Debt Instrument, Credit Rating | Caa1/CC |
Number of Banks (in banks) | Bank | 56 |
Deferrals and Defaults as a % of Current Collateral | 19.72% |
Excess Subordination as a % of Current Performing Collateral | 43.57% |
Pooled Trust Preferred Collateralized Debt Obligations [Member] | Mezzanine [Member] | MMCap I [Member] |  |
Impairment Of Investment Securities [Line Items] |  |
Book Value | $ 208 |
Securities available for sale, at fair value | 297 |
Unrealized Gain (Loss) | $ 89 |
Debt Instrument, Credit Rating | Ca/C |
Number of Banks (in banks) | Bank | 8 |
Deferrals and Defaults as a % of Current Collateral | 58.11% |
Excess Subordination as a % of Current Performing Collateral | 84.08% |

X
- Definition Available for sale securities book value. + References No definition available. + Details
Name: | fcf_AvailableForSaleSecuritiesBookValue
Namespace Prefix: | fcf_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Deferrals and defaults as a percentage of current collateral. + References No definition available. + Details
Name: | fcf_DeferralsAndDefaultsAsPercentageOfCurrentCollateral
Namespace Prefix: | fcf_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Excess subordination as a percentage of current performing collateral. + References No definition available. + Details
Name: | fcf_ExcessSubordinationAsPercentageOfCurrentPerformingCollateral
Namespace Prefix: | fcf_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Impairment Of Investment Securities [Line Items] + References No definition available. + Details
Name: | fcf_ImpairmentOfInvestmentSecuritiesLineItems
Namespace Prefix: | fcf_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Pooled trust preferred collateralized debt obligations in number of banks. + References No definition available. + Details
Name: | fcf_PooledTrustPreferredCollateralizedDebtObligationsInNumberOfBanks
Namespace Prefix: | fcf_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount before tax of unrealized loss in accumulated other comprehensive income (AOCI) on investments in debt securities classified as available-for-sale. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27161-111563 + Details
Name: | us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=51813488&loc=d3e22054-111558 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 5 -Subparagraph (aa) -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27232-111563 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=49167202&loc=d3e26610-111562 + Details
Name: | us-gaap_AvailableForSaleSecurities
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Description of the credit rating indicative of likelihood of repayment of the debt instrument given by a credit rating agency (for example, Standard and Poor's, Moody's, Fitch). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21475-112644 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 22 -Article 5 + Details
Name: | us-gaap_DebtInstrumentCreditRating
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | us-gaap_DebtSecurityAxis=us-gaap_TrustPreferredSecuritiesSubjectToMandatoryRedemptionMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_EligibleItemOrGroupForFairValueOptionAxis=fcf_MezzanineMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis=fcf_PreTslIvMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis=fcf_PreTslViiMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis=fcf_PreTslViiiMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis=fcf_PreTslIxMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis=fcf_PreTslXMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis=fcf_PreTslXiiMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis=fcf_PreTslXiiiMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis=fcf_PreTslXivMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis=fcf_MmcapIMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |