Name:	fnlc_FinancingReceivableLoansClassifiedAsTroubledDebtRestructuringsThatAreInvolvedInBankruptcy
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Carrying amount of loans classified as troubled debt restructurings that were on non-accrual status as of the balance sheet date.

No definition available.

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The number of financing receivables that have been modified by troubled debt restructurings during the current period.

No definition available.

Name:	fnlc_FinancingReceivableModificationsNumberOfContractsDuringPeriod
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The number of financing receivables greater than 30 days past due that have been modified by troubled debt restructurings and that have been placed in the TDR status in the previous 12 months.

No definition available.

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Financing Receivable, Modifications, Number Of Contracts Involved In Bankruptcy During Period

No definition available.

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The number of loans classified as troubled debt restructurings that were on non-accrual status as of the balance sheet date.

No definition available.

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Financing receivables that are greater than 30 days past due.

No definition available.

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Loans classified as troubled debt restructurings that are involved in foreclosure as of the balance sheet date.

No definition available.

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Data Type:	xbrli:monetaryItemType
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Mortgage Loans in Process of Foreclosure, Number

No definition available.

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Number Of Days Past Due

No definition available.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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Amount of the collateral pledged in support of federal home loan bank advances outstanding.

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Amount of fee received for commitment to originate or purchase financing receivable where likelihood of commitment being exercised is remote, to be recognized as service income.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 310
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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Amortized cost excluding accrued interest, before allowance for credit loss, of financing receivable. Excludes net investment in lease.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
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Number of financing receivables that have been modified by troubled debt restructurings.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
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Accumulated amortized cost of financing receivable modified for debtor experiencing financial difficulty.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
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Recorded investment of consumer mortgage loan receivables secured by residential real estate properties for which formal foreclosure proceedings are in process.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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