Other Operating Income and Expense (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Other operating expense
Advertising and marketing expense	$ 1,022us-gaap_MarketingAndAdvertisingExpense	$ 1,117us-gaap_MarketingAndAdvertisingExpense	$ 935us-gaap_MarketingAndAdvertisingExpense
Accounting and auditing expenses	746us-gaap_ProfessionalFees	674us-gaap_ProfessionalFees	630us-gaap_ProfessionalFees
ATM and interchange expense	760fnlc_AtmAndInterchangeExpense	778fnlc_AtmAndInterchangeExpense	940fnlc_AtmAndInterchangeExpense
Legal fees and expenses	769fnlc_LegalFeesAndExpenses	482fnlc_LegalFeesAndExpenses	715fnlc_LegalFeesAndExpenses
Collections/Foreclosures/Other Real Estate Owned Expense
Other operating expense
Collections/foreclosures/ other real estate owned expense	657	878	606
ATM And Debit Card Income
Other operating income
ATM and debit card income	$ 2,630	$ 2,440	$ 1,994

Fees incurred from processing ATM and debit card transaction fees.

No definition available.

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- Definition

Legal fees and expenses.

+ References

No definition available.

+ Details

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- Details

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- Definition

The total expense recognized in the period for promotion, public relations, and brand or product advertising.

+ References

+ Details

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- Definition

The total amount of other operating cost and expense items that are associated with the entity's normal revenue producing operation.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.3)

-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 3

-Article 5

+ Details

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- Definition

The total amount of other operating income, the components of which are not separately disclosed on the income statement, from items that are associated with the entity's normal revenue producing operation.

+ References

+ Details

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- Definition

A fee charged for services from professionals such as doctors, lawyers and accountants. The term is often expanded to include other professions, for example, pharmacists charging to maintain a medicinal profile of a client or customer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 946

-SubTopic 225

-Section S99

-Paragraph 1

-Subparagraph (SX 210.6-07.2(a),(b),(c),(d))

-URI http://asc.fasb.org/extlink&oid=6488393&loc=d3e606610-122999

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 946

-SubTopic 225

-Section 45

-Paragraph 3

-Subparagraph (k)

-URI http://asc.fasb.org/extlink&oid=6488370&loc=d3e13550-115849

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