XML 78 R51.htm IDEA: XBRL DOCUMENT v2.4.1.9
Allowance for Loan Losses - Financing Receivable and Allowance Element by Class (Details) (USD $)
In Thousands, unless otherwise specified
Mar. 31, 2015
Dec. 31, 2014
Mar. 31, 2014
Dec. 31, 2013
Accounts, Notes, Loans and Financing Receivable [Line Items]        
Allowance for loan losses $ 10,196us-gaap_LoansAndLeasesReceivableAllowance $ 10,344us-gaap_LoansAndLeasesReceivableAllowance $ 11,655us-gaap_LoansAndLeasesReceivableAllowance $ 11,514us-gaap_LoansAndLeasesReceivableAllowance
Specific Reserves on Loans Evaluated Individually for Impairment        
Accounts, Notes, Loans and Financing Receivable [Line Items]        
Allowance for loan losses 1,436us-gaap_LoansAndLeasesReceivableAllowance
/ fnlc_FinancingReceivableInformationByTypeOfReserveAxis
= fnlc_SpecificReservesEvaluatedIndividuallyForImpairmentMember		 1,803us-gaap_LoansAndLeasesReceivableAllowance
/ fnlc_FinancingReceivableInformationByTypeOfReserveAxis
= fnlc_SpecificReservesEvaluatedIndividuallyForImpairmentMember		 2,786us-gaap_LoansAndLeasesReceivableAllowance
/ fnlc_FinancingReceivableInformationByTypeOfReserveAxis
= fnlc_SpecificReservesEvaluatedIndividuallyForImpairmentMember		  
General Reserves on Loans Based on Historical Loss Experience        
Accounts, Notes, Loans and Financing Receivable [Line Items]        
Allowance for loan losses 3,114us-gaap_LoansAndLeasesReceivableAllowance
/ fnlc_FinancingReceivableInformationByTypeOfReserveAxis
= fnlc_GeneralReservesBasedOnHistoricalLossExperienceMember		 3,282us-gaap_LoansAndLeasesReceivableAllowance
/ fnlc_FinancingReceivableInformationByTypeOfReserveAxis
= fnlc_GeneralReservesBasedOnHistoricalLossExperienceMember		 3,530us-gaap_LoansAndLeasesReceivableAllowance
/ fnlc_FinancingReceivableInformationByTypeOfReserveAxis
= fnlc_GeneralReservesBasedOnHistoricalLossExperienceMember		  
Reserves for Qualitative Factors        
Accounts, Notes, Loans and Financing Receivable [Line Items]        
Allowance for loan losses 3,805us-gaap_LoansAndLeasesReceivableAllowance
/ fnlc_FinancingReceivableInformationByTypeOfReserveAxis
= fnlc_ReserveForQualitativeFactorsMember		 3,597us-gaap_LoansAndLeasesReceivableAllowance
/ fnlc_FinancingReceivableInformationByTypeOfReserveAxis
= fnlc_ReserveForQualitativeFactorsMember		 3,509us-gaap_LoansAndLeasesReceivableAllowance
/ fnlc_FinancingReceivableInformationByTypeOfReserveAxis
= fnlc_ReserveForQualitativeFactorsMember		  
Unallocated Reserves        
Accounts, Notes, Loans and Financing Receivable [Line Items]        
Allowance for loan losses 1,841us-gaap_LoansAndLeasesReceivableAllowance
/ fnlc_FinancingReceivableInformationByTypeOfReserveAxis
= fnlc_UnallocatedReservesMember		 1,662us-gaap_LoansAndLeasesReceivableAllowance
/ fnlc_FinancingReceivableInformationByTypeOfReserveAxis
= fnlc_UnallocatedReservesMember		 1,830us-gaap_LoansAndLeasesReceivableAllowance
/ fnlc_FinancingReceivableInformationByTypeOfReserveAxis
= fnlc_UnallocatedReservesMember		  
Commercial real estate        
Accounts, Notes, Loans and Financing Receivable [Line Items]        
Allowance for loan losses 3,117us-gaap_LoansAndLeasesReceivableAllowance
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= us-gaap_CommercialRealEstatePortfolioSegmentMember		 3,532us-gaap_LoansAndLeasesReceivableAllowance
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= us-gaap_CommercialRealEstatePortfolioSegmentMember		 4,500us-gaap_LoansAndLeasesReceivableAllowance
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= us-gaap_CommercialRealEstatePortfolioSegmentMember		 4,602us-gaap_LoansAndLeasesReceivableAllowance
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= us-gaap_CommercialRealEstatePortfolioSegmentMember
Commercial real estate | Specific Reserves on Loans Evaluated Individually for Impairment        
Accounts, Notes, Loans and Financing Receivable [Line Items]        
Allowance for loan losses 248us-gaap_LoansAndLeasesReceivableAllowance
/ fnlc_FinancingReceivableInformationByTypeOfReserveAxis
= fnlc_SpecificReservesEvaluatedIndividuallyForImpairmentMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= us-gaap_CommercialRealEstatePortfolioSegmentMember		 346us-gaap_LoansAndLeasesReceivableAllowance
/ fnlc_FinancingReceivableInformationByTypeOfReserveAxis
= fnlc_SpecificReservesEvaluatedIndividuallyForImpairmentMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= us-gaap_CommercialRealEstatePortfolioSegmentMember		 1,019us-gaap_LoansAndLeasesReceivableAllowance
/ fnlc_FinancingReceivableInformationByTypeOfReserveAxis
= fnlc_SpecificReservesEvaluatedIndividuallyForImpairmentMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= us-gaap_CommercialRealEstatePortfolioSegmentMember		  
Commercial real estate | General Reserves on Loans Based on Historical Loss Experience        
Accounts, Notes, Loans and Financing Receivable [Line Items]        
Allowance for loan losses 1,094us-gaap_LoansAndLeasesReceivableAllowance
/ fnlc_FinancingReceivableInformationByTypeOfReserveAxis
= fnlc_GeneralReservesBasedOnHistoricalLossExperienceMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= us-gaap_CommercialRealEstatePortfolioSegmentMember		 1,444us-gaap_LoansAndLeasesReceivableAllowance
/ fnlc_FinancingReceivableInformationByTypeOfReserveAxis
= fnlc_GeneralReservesBasedOnHistoricalLossExperienceMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= us-gaap_CommercialRealEstatePortfolioSegmentMember		 1,707us-gaap_LoansAndLeasesReceivableAllowance
/ fnlc_FinancingReceivableInformationByTypeOfReserveAxis
= fnlc_GeneralReservesBasedOnHistoricalLossExperienceMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= us-gaap_CommercialRealEstatePortfolioSegmentMember		  
Commercial real estate | Reserves for Qualitative Factors        
Accounts, Notes, Loans and Financing Receivable [Line Items]        
Allowance for loan losses 1,775us-gaap_LoansAndLeasesReceivableAllowance
/ fnlc_FinancingReceivableInformationByTypeOfReserveAxis
= fnlc_ReserveForQualitativeFactorsMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= us-gaap_CommercialRealEstatePortfolioSegmentMember		 1,742us-gaap_LoansAndLeasesReceivableAllowance
/ fnlc_FinancingReceivableInformationByTypeOfReserveAxis
= fnlc_ReserveForQualitativeFactorsMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= us-gaap_CommercialRealEstatePortfolioSegmentMember		 1,774us-gaap_LoansAndLeasesReceivableAllowance
/ fnlc_FinancingReceivableInformationByTypeOfReserveAxis
= fnlc_ReserveForQualitativeFactorsMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= us-gaap_CommercialRealEstatePortfolioSegmentMember		  
Commercial construction        
Accounts, Notes, Loans and Financing Receivable [Line Items]        
Allowance for loan losses 807us-gaap_LoansAndLeasesReceivableAllowance
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= fnlc_CommercialConstructionMember		 823us-gaap_LoansAndLeasesReceivableAllowance
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= fnlc_CommercialConstructionMember		 590us-gaap_LoansAndLeasesReceivableAllowance
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= fnlc_CommercialConstructionMember		 575us-gaap_LoansAndLeasesReceivableAllowance
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= fnlc_CommercialConstructionMember
Commercial construction | Specific Reserves on Loans Evaluated Individually for Impairment        
Accounts, Notes, Loans and Financing Receivable [Line Items]        
Allowance for loan losses 396us-gaap_LoansAndLeasesReceivableAllowance
/ fnlc_FinancingReceivableInformationByTypeOfReserveAxis
= fnlc_SpecificReservesEvaluatedIndividuallyForImpairmentMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= fnlc_CommercialConstructionMember		 413us-gaap_LoansAndLeasesReceivableAllowance
/ fnlc_FinancingReceivableInformationByTypeOfReserveAxis
= fnlc_SpecificReservesEvaluatedIndividuallyForImpairmentMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= fnlc_CommercialConstructionMember		 276us-gaap_LoansAndLeasesReceivableAllowance
/ fnlc_FinancingReceivableInformationByTypeOfReserveAxis
= fnlc_SpecificReservesEvaluatedIndividuallyForImpairmentMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= fnlc_CommercialConstructionMember		  
Commercial construction | General Reserves on Loans Based on Historical Loss Experience        
Accounts, Notes, Loans and Financing Receivable [Line Items]        
Allowance for loan losses 157us-gaap_LoansAndLeasesReceivableAllowance
/ fnlc_FinancingReceivableInformationByTypeOfReserveAxis
= fnlc_GeneralReservesBasedOnHistoricalLossExperienceMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= fnlc_CommercialConstructionMember		 186us-gaap_LoansAndLeasesReceivableAllowance
/ fnlc_FinancingReceivableInformationByTypeOfReserveAxis
= fnlc_GeneralReservesBasedOnHistoricalLossExperienceMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= fnlc_CommercialConstructionMember		 154us-gaap_LoansAndLeasesReceivableAllowance
/ fnlc_FinancingReceivableInformationByTypeOfReserveAxis
= fnlc_GeneralReservesBasedOnHistoricalLossExperienceMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= fnlc_CommercialConstructionMember		  
Commercial construction | Reserves for Qualitative Factors        
Accounts, Notes, Loans and Financing Receivable [Line Items]        
Allowance for loan losses 254us-gaap_LoansAndLeasesReceivableAllowance
/ fnlc_FinancingReceivableInformationByTypeOfReserveAxis
= fnlc_ReserveForQualitativeFactorsMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= fnlc_CommercialConstructionMember		 224us-gaap_LoansAndLeasesReceivableAllowance
/ fnlc_FinancingReceivableInformationByTypeOfReserveAxis
= fnlc_ReserveForQualitativeFactorsMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= fnlc_CommercialConstructionMember		 160us-gaap_LoansAndLeasesReceivableAllowance
/ fnlc_FinancingReceivableInformationByTypeOfReserveAxis
= fnlc_ReserveForQualitativeFactorsMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= fnlc_CommercialConstructionMember		  
Commercial other        
Accounts, Notes, Loans and Financing Receivable [Line Items]        
Allowance for loan losses 1,714us-gaap_LoansAndLeasesReceivableAllowance
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= fnlc_CommercialOtherMember		 1,505us-gaap_LoansAndLeasesReceivableAllowance
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= fnlc_CommercialOtherMember		 2,241us-gaap_LoansAndLeasesReceivableAllowance
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= fnlc_CommercialOtherMember		 2,276us-gaap_LoansAndLeasesReceivableAllowance
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= fnlc_CommercialOtherMember
Commercial other | Specific Reserves on Loans Evaluated Individually for Impairment        
Accounts, Notes, Loans and Financing Receivable [Line Items]        
Allowance for loan losses 347us-gaap_LoansAndLeasesReceivableAllowance
/ fnlc_FinancingReceivableInformationByTypeOfReserveAxis
= fnlc_SpecificReservesEvaluatedIndividuallyForImpairmentMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= fnlc_CommercialOtherMember		 129us-gaap_LoansAndLeasesReceivableAllowance
/ fnlc_FinancingReceivableInformationByTypeOfReserveAxis
= fnlc_SpecificReservesEvaluatedIndividuallyForImpairmentMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= fnlc_CommercialOtherMember		 834us-gaap_LoansAndLeasesReceivableAllowance
/ fnlc_FinancingReceivableInformationByTypeOfReserveAxis
= fnlc_SpecificReservesEvaluatedIndividuallyForImpairmentMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= fnlc_CommercialOtherMember		  
Commercial other | General Reserves on Loans Based on Historical Loss Experience        
Accounts, Notes, Loans and Financing Receivable [Line Items]        
Allowance for loan losses 521us-gaap_LoansAndLeasesReceivableAllowance
/ fnlc_FinancingReceivableInformationByTypeOfReserveAxis
= fnlc_GeneralReservesBasedOnHistoricalLossExperienceMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= fnlc_CommercialOtherMember		 624us-gaap_LoansAndLeasesReceivableAllowance
/ fnlc_FinancingReceivableInformationByTypeOfReserveAxis
= fnlc_GeneralReservesBasedOnHistoricalLossExperienceMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= fnlc_CommercialOtherMember		 690us-gaap_LoansAndLeasesReceivableAllowance
/ fnlc_FinancingReceivableInformationByTypeOfReserveAxis
= fnlc_GeneralReservesBasedOnHistoricalLossExperienceMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= fnlc_CommercialOtherMember		  
Commercial other | Reserves for Qualitative Factors        
Accounts, Notes, Loans and Financing Receivable [Line Items]        
Allowance for loan losses 846us-gaap_LoansAndLeasesReceivableAllowance
/ fnlc_FinancingReceivableInformationByTypeOfReserveAxis
= fnlc_ReserveForQualitativeFactorsMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= fnlc_CommercialOtherMember		 752us-gaap_LoansAndLeasesReceivableAllowance
/ fnlc_FinancingReceivableInformationByTypeOfReserveAxis
= fnlc_ReserveForQualitativeFactorsMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= fnlc_CommercialOtherMember		 717us-gaap_LoansAndLeasesReceivableAllowance
/ fnlc_FinancingReceivableInformationByTypeOfReserveAxis
= fnlc_ReserveForQualitativeFactorsMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= fnlc_CommercialOtherMember		  
Municipal        
Accounts, Notes, Loans and Financing Receivable [Line Items]        
Allowance for loan losses 16us-gaap_LoansAndLeasesReceivableAllowance
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= fnlc_MunicipalMember		 15us-gaap_LoansAndLeasesReceivableAllowance
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= fnlc_MunicipalMember		 15us-gaap_LoansAndLeasesReceivableAllowance
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= fnlc_MunicipalMember		 15us-gaap_LoansAndLeasesReceivableAllowance
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= fnlc_MunicipalMember
Municipal | Specific Reserves on Loans Evaluated Individually for Impairment        
Accounts, Notes, Loans and Financing Receivable [Line Items]        
Allowance for loan losses   0us-gaap_LoansAndLeasesReceivableAllowance
/ fnlc_FinancingReceivableInformationByTypeOfReserveAxis
= fnlc_SpecificReservesEvaluatedIndividuallyForImpairmentMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= fnlc_MunicipalMember		 0us-gaap_LoansAndLeasesReceivableAllowance
/ fnlc_FinancingReceivableInformationByTypeOfReserveAxis
= fnlc_SpecificReservesEvaluatedIndividuallyForImpairmentMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= fnlc_MunicipalMember		  
Municipal | General Reserves on Loans Based on Historical Loss Experience        
Accounts, Notes, Loans and Financing Receivable [Line Items]        
Allowance for loan losses   0us-gaap_LoansAndLeasesReceivableAllowance
/ fnlc_FinancingReceivableInformationByTypeOfReserveAxis
= fnlc_GeneralReservesBasedOnHistoricalLossExperienceMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= fnlc_MunicipalMember		 0us-gaap_LoansAndLeasesReceivableAllowance
/ fnlc_FinancingReceivableInformationByTypeOfReserveAxis
= fnlc_GeneralReservesBasedOnHistoricalLossExperienceMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= fnlc_MunicipalMember		  
Municipal | Reserves for Qualitative Factors        
Accounts, Notes, Loans and Financing Receivable [Line Items]        
Allowance for loan losses 16us-gaap_LoansAndLeasesReceivableAllowance
/ fnlc_FinancingReceivableInformationByTypeOfReserveAxis
= fnlc_ReserveForQualitativeFactorsMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= fnlc_MunicipalMember		 15us-gaap_LoansAndLeasesReceivableAllowance
/ fnlc_FinancingReceivableInformationByTypeOfReserveAxis
= fnlc_ReserveForQualitativeFactorsMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= fnlc_MunicipalMember		 15us-gaap_LoansAndLeasesReceivableAllowance
/ fnlc_FinancingReceivableInformationByTypeOfReserveAxis
= fnlc_ReserveForQualitativeFactorsMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= fnlc_MunicipalMember		  
Residential term        
Accounts, Notes, Loans and Financing Receivable [Line Items]        
Allowance for loan losses 1,108us-gaap_LoansAndLeasesReceivableAllowance
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= fnlc_ResidentialTermMember		 1,185us-gaap_LoansAndLeasesReceivableAllowance
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= fnlc_ResidentialTermMember		 1,232us-gaap_LoansAndLeasesReceivableAllowance
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= fnlc_ResidentialTermMember		 1,099us-gaap_LoansAndLeasesReceivableAllowance
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= fnlc_ResidentialTermMember
Residential term | Specific Reserves on Loans Evaluated Individually for Impairment        
Accounts, Notes, Loans and Financing Receivable [Line Items]        
Allowance for loan losses 421us-gaap_LoansAndLeasesReceivableAllowance
/ fnlc_FinancingReceivableInformationByTypeOfReserveAxis
= fnlc_SpecificReservesEvaluatedIndividuallyForImpairmentMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= fnlc_ResidentialTermMember		 519us-gaap_LoansAndLeasesReceivableAllowance
/ fnlc_FinancingReceivableInformationByTypeOfReserveAxis
= fnlc_SpecificReservesEvaluatedIndividuallyForImpairmentMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= fnlc_ResidentialTermMember		 574us-gaap_LoansAndLeasesReceivableAllowance
/ fnlc_FinancingReceivableInformationByTypeOfReserveAxis
= fnlc_SpecificReservesEvaluatedIndividuallyForImpairmentMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= fnlc_ResidentialTermMember		  
Residential term | General Reserves on Loans Based on Historical Loss Experience        
Accounts, Notes, Loans and Financing Receivable [Line Items]        
Allowance for loan losses 298us-gaap_LoansAndLeasesReceivableAllowance
/ fnlc_FinancingReceivableInformationByTypeOfReserveAxis
= fnlc_GeneralReservesBasedOnHistoricalLossExperienceMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= fnlc_ResidentialTermMember		 297us-gaap_LoansAndLeasesReceivableAllowance
/ fnlc_FinancingReceivableInformationByTypeOfReserveAxis
= fnlc_GeneralReservesBasedOnHistoricalLossExperienceMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= fnlc_ResidentialTermMember		 303us-gaap_LoansAndLeasesReceivableAllowance
/ fnlc_FinancingReceivableInformationByTypeOfReserveAxis
= fnlc_GeneralReservesBasedOnHistoricalLossExperienceMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= fnlc_ResidentialTermMember		  
Residential term | Reserves for Qualitative Factors        
Accounts, Notes, Loans and Financing Receivable [Line Items]        
Allowance for loan losses 389us-gaap_LoansAndLeasesReceivableAllowance
/ fnlc_FinancingReceivableInformationByTypeOfReserveAxis
= fnlc_ReserveForQualitativeFactorsMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= fnlc_ResidentialTermMember		 369us-gaap_LoansAndLeasesReceivableAllowance
/ fnlc_FinancingReceivableInformationByTypeOfReserveAxis
= fnlc_ReserveForQualitativeFactorsMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= fnlc_ResidentialTermMember		 355us-gaap_LoansAndLeasesReceivableAllowance
/ fnlc_FinancingReceivableInformationByTypeOfReserveAxis
= fnlc_ReserveForQualitativeFactorsMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= fnlc_ResidentialTermMember		  
Residential construction        
Accounts, Notes, Loans and Financing Receivable [Line Items]        
Allowance for loan losses 23us-gaap_LoansAndLeasesReceivableAllowance
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= fnlc_ResidentialConstructionMember		 20us-gaap_LoansAndLeasesReceivableAllowance
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= fnlc_ResidentialConstructionMember		 22us-gaap_LoansAndLeasesReceivableAllowance
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= fnlc_ResidentialConstructionMember		 21us-gaap_LoansAndLeasesReceivableAllowance
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= fnlc_ResidentialConstructionMember
Residential construction | Specific Reserves on Loans Evaluated Individually for Impairment        
Accounts, Notes, Loans and Financing Receivable [Line Items]        
Allowance for loan losses 0us-gaap_LoansAndLeasesReceivableAllowance
/ fnlc_FinancingReceivableInformationByTypeOfReserveAxis
= fnlc_SpecificReservesEvaluatedIndividuallyForImpairmentMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= fnlc_ResidentialConstructionMember		 0us-gaap_LoansAndLeasesReceivableAllowance
/ fnlc_FinancingReceivableInformationByTypeOfReserveAxis
= fnlc_SpecificReservesEvaluatedIndividuallyForImpairmentMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= fnlc_ResidentialConstructionMember		 0us-gaap_LoansAndLeasesReceivableAllowance
/ fnlc_FinancingReceivableInformationByTypeOfReserveAxis
= fnlc_SpecificReservesEvaluatedIndividuallyForImpairmentMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= fnlc_ResidentialConstructionMember		  
Residential construction | General Reserves on Loans Based on Historical Loss Experience        
Accounts, Notes, Loans and Financing Receivable [Line Items]        
Allowance for loan losses 10us-gaap_LoansAndLeasesReceivableAllowance
/ fnlc_FinancingReceivableInformationByTypeOfReserveAxis
= fnlc_GeneralReservesBasedOnHistoricalLossExperienceMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= fnlc_ResidentialConstructionMember		 9us-gaap_LoansAndLeasesReceivableAllowance
/ fnlc_FinancingReceivableInformationByTypeOfReserveAxis
= fnlc_GeneralReservesBasedOnHistoricalLossExperienceMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= fnlc_ResidentialConstructionMember		 10us-gaap_LoansAndLeasesReceivableAllowance
/ fnlc_FinancingReceivableInformationByTypeOfReserveAxis
= fnlc_GeneralReservesBasedOnHistoricalLossExperienceMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= fnlc_ResidentialConstructionMember		  
Residential construction | Reserves for Qualitative Factors        
Accounts, Notes, Loans and Financing Receivable [Line Items]        
Allowance for loan losses 13us-gaap_LoansAndLeasesReceivableAllowance
/ fnlc_FinancingReceivableInformationByTypeOfReserveAxis
= fnlc_ReserveForQualitativeFactorsMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
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/ fnlc_FinancingReceivableInformationByTypeOfReserveAxis
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Home equity line of credit        
Accounts, Notes, Loans and Financing Receivable [Line Items]        
Allowance for loan losses 1,044us-gaap_LoansAndLeasesReceivableAllowance
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Home equity line of credit | Specific Reserves on Loans Evaluated Individually for Impairment        
Accounts, Notes, Loans and Financing Receivable [Line Items]        
Allowance for loan losses 24us-gaap_LoansAndLeasesReceivableAllowance
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Home equity line of credit | General Reserves on Loans Based on Historical Loss Experience        
Accounts, Notes, Loans and Financing Receivable [Line Items]        
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Home equity line of credit | Reserves for Qualitative Factors        
Accounts, Notes, Loans and Financing Receivable [Line Items]        
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Consumer        
Accounts, Notes, Loans and Financing Receivable [Line Items]        
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Accounts, Notes, Loans and Financing Receivable [Line Items]        
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Accounts, Notes, Loans and Financing Receivable [Line Items]        
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Consumer | Reserves for Qualitative Factors        
Accounts, Notes, Loans and Financing Receivable [Line Items]        
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Unallocated        
Accounts, Notes, Loans and Financing Receivable [Line Items]        
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Unallocated | Unallocated Reserves        
Accounts, Notes, Loans and Financing Receivable [Line Items]        
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