| **Investment Securities - Analysis of Amortized Cost and Estimated Fair Values of Securities Available for Sale (Detail) (USD $)In Thousands, unless otherwise specified** | 12 Months Ended                                                                                                                                                                                                                                                       |
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| **Investment Securities [Line Items]**                                                                                                                                     |                                                                                                                                                                                                                                                                  |   |
| Amortized Cost                                                                                                                                                             | $ 1,317,318us-gaap_AvailableForSaleSecuritiesAmortizedCost                                                                                                                                                                                                            | $ 1,350,466us-gaap_AvailableForSaleSecuritiesAmortizedCost |
| Gross Unrealized Gains                                                                                                                                                     | 16,921us-gaap_AvailableForSaleSecuritiesGrossUnrealizedGains                                                                                                                                                                                                          | 15,565us-gaap_AvailableForSaleSecuritiesGrossUnrealizedGains |
| Gross Unrealized Losses                                                                                                                                                    | (24,420)us-gaap_AvailableForSaleSecuritiesGrossUnrealizedLoss                                                                                                                                                                                                         | (47,666)us-gaap_AvailableForSaleSecuritiesGrossUnrealizedLoss |
| Estimated Fair Value of Available for Sale                                                                                                                                 | 1,309,819us-gaap_AvailableForSaleSecurities                                                                                                                                                                                                                           | 1,318,365us-gaap_AvailableForSaleSecurities |
| US States and Political Subdivisions Debt Securities [Member]                                                                                                              |                                                                                                                                                                                                                                                                  |   |
| **Investment Securities [Line Items]**                                                                                                                                     |                                                                                                                                                                                                                                                                  |   |
| Amortized Cost                                                                                                                                                             | 27,058us-gaap_AvailableForSaleSecuritiesAmortizedCost/ us-gaap_FairValueByLiabilityClassAxis= us-gaap_USStatesAndPoliticalSubdivisionsMember                                                                                                                          | 80us-gaap_AvailableForSaleSecuritiesAmortizedCost/ us-gaap_FairValueByLiabilityClassAxis= us-gaap_USStatesAndPoliticalSubdivisionsMember |
| Gross Unrealized Gains                                                                                                                                                     | 362us-gaap_AvailableForSaleSecuritiesGrossUnrealizedGains/ us-gaap_FairValueByLiabilityClassAxis= us-gaap_USStatesAndPoliticalSubdivisionsMember                                                                                                                      | 0us-gaap_AvailableForSaleSecuritiesGrossUnrealizedGains/ us-gaap_FairValueByLiabilityClassAxis= us-gaap_USStatesAndPoliticalSubdivisionsMember |
| Gross Unrealized Losses                                                                                                                                                    | (43)us-gaap_AvailableForSaleSecuritiesGrossUnrealizedLoss/ us-gaap_FairValueByLiabilityClassAxis= us-gaap_USStatesAndPoliticalSubdivisionsMember                                                                                                                      | 0us-gaap_AvailableForSaleSecuritiesGrossUnrealizedLoss/ us-gaap_FairValueByLiabilityClassAxis= us-gaap_USStatesAndPoliticalSubdivisionsMember |
| Estimated Fair Value of Available for Sale                                                                                                                                 | 27,377us-gaap_AvailableForSaleSecurities/ us-gaap_FairValueByLiabilityClassAxis= us-gaap_USStatesAndPoliticalSubdivisionsMember                                                                                                                                       | 80us-gaap_AvailableForSaleSecurities/ us-gaap_FairValueByLiabilityClassAxis= us-gaap_USStatesAndPoliticalSubdivisionsMember |
| Corporate Securities [Member]                                                                                                                                              |                                                                                                                                                                                                                                                                  |   |
| **Investment Securities [Line Items]**                                                                                                                                     |                                                                                                                                                                                                                                                                  |   |
| Amortized Cost                                                                                                                                                             | 6,682us-gaap_AvailableForSaleSecuritiesAmortizedCost/ us-gaap_FairValueByLiabilityClassAxis= us-gaap_CorporateDebtSecuritiesMember                                                                                                                                    | 6,693us-gaap_AvailableForSaleSecuritiesAmortizedCost/ us-gaap_FairValueByLiabilityClassAxis= us-gaap_CorporateDebtSecuritiesMember |
| Gross Unrealized Gains                                                                                                                                                     | 573us-gaap_AvailableForSaleSecuritiesGrossUnrealizedGains/ us-gaap_FairValueByLiabilityClassAxis= us-gaap_CorporateDebtSecuritiesMember                                                                                                                               | 328us-gaap_AvailableForSaleSecuritiesGrossUnrealizedGains/ us-gaap_FairValueByLiabilityClassAxis= us-gaap_CorporateDebtSecuritiesMember |
| Gross Unrealized Losses                                                                                                                                                    | 0us-gaap_AvailableForSaleSecuritiesGrossUnrealizedLoss/ us-gaap_FairValueByLiabilityClassAxis= us-gaap_CorporateDebtSecuritiesMember                                                                                                                                  | 0us-gaap_AvailableForSaleSecuritiesGrossUnrealizedLoss/ us-gaap_FairValueByLiabilityClassAxis= us-gaap_CorporateDebtSecuritiesMember |
| Estimated Fair Value of Available for Sale                                                                                                                                 | 7,255us-gaap_AvailableForSaleSecurities/ us-gaap_FairValueByLiabilityClassAxis= us-gaap_CorporateDebtSecuritiesMember                                                                                                                                                 | 7,021us-gaap_AvailableForSaleSecurities/ us-gaap_FairValueByLiabilityClassAxis= us-gaap_CorporateDebtSecuritiesMember |
| Pooled Trust Preferred Collateralized Debt Obligations [Member]                                                                                                            |                                                                                                                                                                                                                                                                  |   |
| **Investment Securities [Line Items]**                                                                                                                                     |                                                                                                                                                                                                                                                                  |   |
| Amortized Cost                                                                                                                                                             | 41,926us-gaap_AvailableForSaleSecuritiesAmortizedCost/ us-gaap_FairValueByLiabilityClassAxis= us-gaap_TrustPreferredSecuritiesSubjectToMandatoryRedemptionMember                                                                                                      | 42,040us-gaap_AvailableForSaleSecuritiesAmortizedCost/ us-gaap_FairValueByLiabilityClassAxis= us-gaap_TrustPreferredSecuritiesSubjectToMandatoryRedemptionMember |
| Gross Unrealized Gains                                                                                                                                                     | 309us-gaap_AvailableForSaleSecuritiesGrossUnrealizedGains/ us-gaap_FairValueByLiabilityClassAxis= us-gaap_TrustPreferredSecuritiesSubjectToMandatoryRedemptionMember                                                                                                  | 0us-gaap_AvailableForSaleSecuritiesGrossUnrealizedGains/ us-gaap_FairValueByLiabilityClassAxis= us-gaap_TrustPreferredSecuritiesSubjectToMandatoryRedemptionMember |
| Gross Unrealized Losses                                                                                                                                                    | (13,236)us-gaap_AvailableForSaleSecuritiesGrossUnrealizedLoss/ us-gaap_FairValueByLiabilityClassAxis= us-gaap_TrustPreferredSecuritiesSubjectToMandatoryRedemptionMember                                                                                              | (18,517)us-gaap_AvailableForSaleSecuritiesGrossUnrealizedLoss/ us-gaap_FairValueByLiabilityClassAxis= us-gaap_TrustPreferredSecuritiesSubjectToMandatoryRedemptionMember |
| Estimated Fair Value of Available for Sale                                                                                                                                 | 28,999us-gaap_AvailableForSaleSecurities/ us-gaap_FairValueByLiabilityClassAxis= us-gaap_TrustPreferredSecuritiesSubjectToMandatoryRedemptionMember                                                                                                                   | 23,523us-gaap_AvailableForSaleSecurities/ us-gaap_FairValueByLiabilityClassAxis= us-gaap_TrustPreferredSecuritiesSubjectToMandatoryRedemptionMember |
| Debt Securities [Member]                                                                                                                                                   |                                                                                                                                                                                                                                                                  |   |
| **Investment Securities [Line Items]**                                                                                                                                     |                                                                                                                                                                                                                                                                  |   |
| Amortized Cost                                                                                                                                                             | 1,315,898us-gaap_AvailableForSaleSecuritiesAmortizedCost/ us-gaap_FairValueByLiabilityClassAxis= us-gaap_DebtSecuritiesMember                                                                                                                                         | 1,349,046us-gaap_AvailableForSaleSecuritiesAmortizedCost/ us-gaap_FairValueByLiabilityClassAxis= us-gaap_DebtSecuritiesMember |
| Gross Unrealized Gains                                                                                                                                                     | 16,921us-gaap_AvailableForSaleSecuritiesGrossUnrealizedGains/ us-gaap_FairValueByLiabilityClassAxis= us-gaap_DebtSecuritiesMember                                                                                                                                     | 15,565us-gaap_AvailableForSaleSecuritiesGrossUnrealizedGains/ us-gaap_FairValueByLiabilityClassAxis= us-gaap_DebtSecuritiesMember |
| Gross Unrealized Losses                                                                                                                                                    | (24,420)us-gaap_AvailableForSaleSecuritiesGrossUnrealizedLoss/ us-gaap_FairValueByLiabilityClassAxis= us-gaap_DebtSecuritiesMember                                                                                                                                    | (47,666)us-gaap_AvailableForSaleSecuritiesGrossUnrealizedLoss/ us-gaap_FairValueByLiabilityClassAxis= us-gaap_DebtSecuritiesMember |
| Estimated Fair Value of Available for Sale                                                                                                                                 | 1,308,399us-gaap_AvailableForSaleSecurities/ us-gaap_FairValueByLiabilityClassAxis= us-gaap_DebtSecuritiesMember                                                                                                                                                      | 1,316,945us-gaap_AvailableForSaleSecurities/ us-gaap_FairValueByLiabilityClassAxis= us-gaap_DebtSecuritiesMember |
| Mortgage - Backed Securities - Residential [Member] | US Government Agencies Debt Securities [Member]                                                                      |                                                                                                                                                                                                                                                                  |   |
| **Investment Securities [Line Items]**                                                                                                                                     |                                                                                                                                                                                                                                                                  |   |
| Amortized Cost                                                                                                                                                             | 23,344us-gaap_AvailableForSaleSecuritiesAmortizedCost/ us-gaap_FairValueByLiabilityClassAxis= us-gaap_USGovernmentAgenciesDebtSecuritiesMember/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_ResidentialMortgageBackedSecuritiesMember                    | 22,639us-gaap_AvailableForSaleSecuritiesAmortizedCost/ us-gaap_FairValueByLiabilityClassAxis= us-gaap_USGovernmentAgenciesDebtSecuritiesMember/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_ResidentialMortgageBackedSecuritiesMember |
| Gross Unrealized Gains                                                                                                                                                     | 2,595us-gaap_AvailableForSaleSecuritiesGrossUnrealizedGains/ us-gaap_FairValueByLiabilityClassAxis= us-gaap_USGovernmentAgenciesDebtSecuritiesMember/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_ResidentialMortgageBackedSecuritiesMember              | 2,624us-gaap_AvailableForSaleSecuritiesGrossUnrealizedGains/ us-gaap_FairValueByLiabilityClassAxis= us-gaap_USGovernmentAgenciesDebtSecuritiesMember/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_ResidentialMortgageBackedSecuritiesMember |
| Gross Unrealized Losses                                                                                                                                                    | (3)us-gaap_AvailableForSaleSecuritiesGrossUnrealizedLoss/ us-gaap_FairValueByLiabilityClassAxis= us-gaap_USGovernmentAgenciesDebtSecuritiesMember/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_ResidentialMortgageBackedSecuritiesMember                 | (59)us-gaap_AvailableForSaleSecuritiesGrossUnrealizedLoss/ us-gaap_FairValueByLiabilityClassAxis= us-gaap_USGovernmentAgenciesDebtSecuritiesMember/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_ResidentialMortgageBackedSecuritiesMember |
| Estimated Fair Value of Available for Sale                                                                                                                                 | 25,936us-gaap_AvailableForSaleSecurities/ us-gaap_FairValueByLiabilityClassAxis= us-gaap_USGovernmentAgenciesDebtSecuritiesMember/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_ResidentialMortgageBackedSecuritiesMember                                 | 25,204us-gaap_AvailableForSaleSecurities/ us-gaap_FairValueByLiabilityClassAxis= us-gaap_USGovernmentAgenciesDebtSecuritiesMember/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_ResidentialMortgageBackedSecuritiesMember |
| Mortgage - Backed Securities - Residential [Member] | Obligations of U.S. Government-Sponsored Enterprises [Member]                                                        |                                                                                                                                                                                                                                                                  |   |
| **Investment Securities [Line Items]**                                                                                                                                     |                                                                                                                                                                                                                                                                  |   |
| Amortized Cost                                                                                                                                                             | 947,635us-gaap_AvailableForSaleSecuritiesAmortizedCost/ us-gaap_FairValueByLiabilityClassAxis= us-gaap_USGovernmentSponsoredEnterprisesDebtSecuritiesMember/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_ResidentialMortgageBackedSecuritiesMember       | 1,009,519us-gaap_AvailableForSaleSecuritiesAmortizedCost/ us-gaap_FairValueByLiabilityClassAxis= us-gaap_USGovernmentSponsoredEnterprisesDebtSecuritiesMember/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_ResidentialMortgageBackedSecuritiesMember |
| Gross Unrealized Gains                                                                                                                                                     | 13,076us-gaap_AvailableForSaleSecuritiesGrossUnrealizedGains/ us-gaap_FairValueByLiabilityClassAxis= us-gaap_USGovernmentSponsoredEnterprisesDebtSecuritiesMember/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_ResidentialMortgageBackedSecuritiesMember | 12,531us-gaap_AvailableForSaleSecuritiesGrossUnrealizedGains/ us-gaap_FairValueByLiabilityClassAxis= us-gaap_USGovernmentSponsoredEnterprisesDebtSecuritiesMember/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_ResidentialMortgageBackedSecuritiesMember |
| Gross Unrealized Losses                                                                                                                                                    | (9,830)us-gaap_AvailableForSaleSecuritiesGrossUnrealizedLoss/ us-gaap_FairValueByLiabilityClassAxis= us-gaap_USGovernmentSponsoredEnterprisesDebtSecuritiesMember/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_ResidentialMortgageBackedSecuritiesMember | (27,163)us-gaap_AvailableForSaleSecuritiesGrossUnrealizedLoss/ us-gaap_FairValueByLiabilityClassAxis= us-gaap_USGovernmentSponsoredEnterprisesDebtSecuritiesMember/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_ResidentialMortgageBackedSecuritiesMember |
| Estimated Fair Value of Available for Sale                                                                                                                                 | 950,881us-gaap_AvailableForSaleSecurities/ us-gaap_FairValueByLiabilityClassAxis= us-gaap_USGovernmentSponsoredEnterprisesDebtSecuritiesMember/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_ResidentialMortgageBackedSecuritiesMember                    | 994,887us-gaap_AvailableForSaleSecurities/ us-gaap_FairValueByLiabilityClassAxis= us-gaap_USGovernmentSponsoredEnterprisesDebtSecuritiesMember/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_ResidentialMortgageBackedSecuritiesMember |
| Mortgage - Backed Securities - Commercial [Member] | Obligations of U.S. Government-Sponsored Enterprises [Member]                                                         |                                                                                                                                                                                                                                                                  |   |
| **Investment Securities [Line Items]**                                                                                                                                     |                                                                                                                                                                                                                                                                  |   |
| Amortized Cost                                                                                                                                                             | 72us-gaap_AvailableForSaleSecuritiesAmortizedCost/ us-gaap_FairValueByLiabilityClassAxis= us-gaap_USGovernmentSponsoredEnterprisesDebtSecuritiesMember/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_CommercialMortgageBackedSecuritiesMember             | 104us-gaap_AvailableForSaleSecuritiesAmortizedCost/ us-gaap_FairValueByLiabilityClassAxis= us-gaap_USGovernmentSponsoredEnterprisesDebtSecuritiesMember/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_CommercialMortgageBackedSecuritiesMember |
| Gross Unrealized Gains                                                                                                                                                     | 2us-gaap_AvailableForSaleSecuritiesGrossUnrealizedGains/ us-gaap_FairValueByLiabilityClassAxis= us-gaap_USGovernmentSponsoredEnterprisesDebtSecuritiesMember/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_CommercialMortgageBackedSecuritiesMember       | 1us-gaap_AvailableForSaleSecuritiesGrossUnrealizedGains/ us-gaap_FairValueByLiabilityClassAxis= us-gaap_USGovernmentSponsoredEnterprisesDebtSecuritiesMember/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_CommercialMortgageBackedSecuritiesMember |
| Gross Unrealized Losses                                                                                                                                                    | 0us-gaap_AvailableForSaleSecuritiesGrossUnrealizedLoss/ us-gaap_FairValueByLiabilityClassAxis= us-gaap_USGovernmentSponsoredEnterprisesDebtSecuritiesMember/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_CommercialMortgageBackedSecuritiesMember        | 0us-gaap_AvailableForSaleSecuritiesGrossUnrealizedLoss/ us-gaap_FairValueByLiabilityClassAxis= us-gaap_USGovernmentSponsoredEnterprisesDebtSecuritiesMember/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_CommercialMortgageBackedSecuritiesMember |
| Estimated Fair Value of Available for Sale                                                                                                                                 | 74us-gaap_AvailableForSaleSecurities/ us-gaap_FairValueByLiabilityClassAxis= us-gaap_USGovernmentSponsoredEnterprisesDebtSecuritiesMember/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_CommercialMortgageBackedSecuritiesMember                          | 105us-gaap_AvailableForSaleSecurities/ us-gaap_FairValueByLiabilityClassAxis= us-gaap_USGovernmentSponsoredEnterprisesDebtSecuritiesMember/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_CommercialMortgageBackedSecuritiesMember |
| Other Government - Sponsored Enterprises [Member] | Obligations of U.S. Government-Sponsored Enterprises [Member]                                                          |                                                                                                                                                                                                                                                                  |   |
| **Investment Securities [Line Items]**                                                                                                                                     |                                                                                                                                                                                                                                                                  |   |
| Amortized Cost                                                                                                                                                             | 269,181us-gaap_AvailableForSaleSecuritiesAmortizedCost/ us-gaap_FairValueByLiabilityClassAxis= us-gaap_USGovernmentSponsoredEnterprisesDebtSecuritiesMember/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= fcf_OtherGovernmentSponsoredEnterprisesMember           | 267,971us-gaap_AvailableForSaleSecuritiesAmortizedCost/ us-gaap_FairValueByLiabilityClassAxis= us-gaap_USGovernmentSponsoredEnterprisesDebtSecuritiesMember/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= fcf_OtherGovernmentSponsoredEnterprisesMember |
| Gross Unrealized Gains                                                                                                                                                     | 4us-gaap_AvailableForSaleSecuritiesGrossUnrealizedGains/ us-gaap_FairValueByLiabilityClassAxis= us-gaap_USGovernmentSponsoredEnterprisesDebtSecuritiesMember/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= fcf_OtherGovernmentSponsoredEnterprisesMember          | 81us-gaap_AvailableForSaleSecuritiesGrossUnrealizedGains/ us-gaap_FairValueByLiabilityClassAxis= us-gaap_USGovernmentSponsoredEnterprisesDebtSecuritiesMember/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= fcf_OtherGovernmentSponsoredEnterprisesMember |
| Gross Unrealized Losses                                                                                                                                                    | (1,308)us-gaap_AvailableForSaleSecuritiesGrossUnrealizedLoss/ us-gaap_FairValueByLiabilityClassAxis= us-gaap_USGovernmentSponsoredEnterprisesDebtSecuritiesMember/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= fcf_OtherGovernmentSponsoredEnterprisesMember     | (1,927)us-gaap_AvailableForSaleSecuritiesGrossUnrealizedLoss/ us-gaap_FairValueByLiabilityClassAxis= us-gaap_USGovernmentSponsoredEnterprisesDebtSecuritiesMember/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= fcf_OtherGovernmentSponsoredEnterprisesMember |
| Estimated Fair Value of Available for Sale                                                                                                                                 | 267,877us-gaap_AvailableForSaleSecurities/ us-gaap_FairValueByLiabilityClassAxis= us-gaap_USGovernmentSponsoredEnterprisesDebtSecuritiesMember/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= fcf_OtherGovernmentSponsoredEnterprisesMember                        | 266,125us-gaap_AvailableForSaleSecurities/ us-gaap_FairValueByLiabilityClassAxis= us-gaap_USGovernmentSponsoredEnterprisesDebtSecuritiesMember/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= fcf_OtherGovernmentSponsoredEnterprisesMember |
| Equities [Member]                                                                                                                                                          |                                                                                                                                                                                                                                                                  |   |
| **Investment Securities [Line Items]**                                                                                                                                     |                                                                                                                                                                                                                                                                  |   |
| Amortized Cost                                                                                                                                                             | 1,420us-gaap_AvailableForSaleSecuritiesAmortizedCost/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_EquitySecuritiesMember                                                                                                                                 | 1,420us-gaap_AvailableForSaleSecuritiesAmortizedCost/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_EquitySecuritiesMember |
| Gross Unrealized Gains                                                                                                                                                     | 0us-gaap_AvailableForSaleSecuritiesGrossUnrealizedGains/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_EquitySecuritiesMember                                                                                                                              | 0us-gaap_AvailableForSaleSecuritiesGrossUnrealizedGains/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_EquitySecuritiesMember |
| Gross Unrealized Losses                                                                                                                                                    | 0us-gaap_AvailableForSaleSecuritiesGrossUnrealizedLoss/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_EquitySecuritiesMember                                                                                                                               | 0us-gaap_AvailableForSaleSecuritiesGrossUnrealizedLoss/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_EquitySecuritiesMember |
| Estimated Fair Value of Available for Sale                                                                                                                                 | $ 1,420us-gaap_AvailableForSaleSecurities/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_EquitySecuritiesMember                                                                                                                                            | $ 1,420us-gaap_AvailableForSaleSecurities/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_EquitySecuritiesMember |

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| - Definition
Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.
+ References
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| - Definition
This item represents the cost of debt and equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any.
+ References
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| - Definition
Amount of unrealized gain before deducting unrealized loss on investments in debt and equity securities classified as available-for-sale securities.
+ References
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| - Definition
Amount of unrealized loss before deducting unrealized gain on investments in available-for-sale securities.
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