Total aggregate intrinsic value on shares exercised.

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The percentage of options vesting five years to total option plan as of the balance sheet date if other than 100 percent.

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The percentage of options vesting two years to total option plan as of the balance sheet date if other than 100 percent.

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Description of the remaining period of time over which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, which may be expressed in a variety of ways (for example, in years, month and year).

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Description of the period of time over which an employee's right to exercise the final tranche of options awarded is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, which may be expressed in a variety of ways (for example, in years, month and year).

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Description of the period of time over which an employee's right to exercise the first tranche of options awarded is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, which may be expressed in a variety of ways (for example, in years, month and year).

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Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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Aggregate number of common shares reserved for future issuance.

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Unrecognized cost of unvested share-based compensation awards.

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Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The total recognized tax benefit related to compensation cost for equity-based payment arrangements recognized in income during the period.

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Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of vested portions of options outstanding and currently exercisable.

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The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

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Weighted average remaining contractual term for vested portions of options outstanding and currently exercisable or convertible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Weighted average price of options that were either forfeited or expired.

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The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan.

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Net number of share options (or share units) granted during the period.

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Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

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Number of options outstanding, including both vested and non-vested options.

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Weighted average price at which option holders acquired shares when converting their stock options into shares.

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Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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Number of share options (or share units) exercised during the current period.

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Stock Options and Stock-Based Compensation (Details) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 1995	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares of common stock reserved for issuance (in shares)						400,000
Vesting Term (In Years)			10 years
Employee Service Share-based Compensation, Tax Benefit from Compensation Expense	$ 1,178,000
Compensation cost recognized for options granted	431,000	214,000
Unrecognized compensation costs	412,000	433,000
Granted in 1995 (in shares)	0
Percentage of options vesting two years (in hundredths)			50.00%fnlc_PercentageOfOptionsVestingTwoYears
Vesting term, option one (in years)			2 years
Percentage of options vesting five years (in hundredths)			50.00%
Vesting term, option two (in years)			5 years
Summary of status and changes of Stock Option Plan [Roll Forward]
Outstanding, beginning of period (in shares)	42,000	42,000
Granted(in shares)	0
Exercised (in shares)	0
Forfeited (in shares)	0
Outstanding, end of period (in shares)	42,000	42,000
Exercisable, end of period (in shares)	42,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Abstract]
Outstanding options, weighted average exercise price, beginning of period (in dollars per share)	$ 18.00
Granted options, weighted average exercise price (in dollars per share)	$ 0.00
Exercised options, weighted average exercise price (in dollars per share)	$ 0.00
Forfeited options, weighted average exercise price (in dollars per share)	$ 0.00
Outstanding options, weighted average exercise price, end of period (in dollars per share)	$ 18.00	$ 18.00
Exercisable options, weighted average exercise price, end of period (in dollars per share)	$ 18.00
Outstanding options, end of period, weighted average remaining contractual term (in years)	1 month
Exercisable options, end of period, weighted average remaining contractual term (in years)	1 month
Exercised options, aggregate intrinsic value	0
Outstanding options, end of period, aggregate intrinsic value	0
Exercisable options, end of period, aggregate intrinsic value	$ 0
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock granted (in shares)	72,684
2011 Plan \| One Year \| Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting Term (In Years)	1 year
2011 Plan \| Two Years \| Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting Term (In Years)	2 years	2 years
2011 Plan \| Four Years \| Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting Term (In Years)				4 years	4 years
Restricted stock granted (in shares)		3,808		2,704	1,500
Remaining Term (In Years)		1 year 1 month 6 days		1 year 2 months 12 days	1 month
2011 Plan \| Restricted Stock \| Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock granted (in shares)	72,684
Remaining Term (In Years)	1 year 10 months 24 days
2011 Plan \| Five Years \| Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting Term (In Years)	5 years	5 years		5 years	5 years
Restricted stock granted (in shares)		14,776		7,996	5,500
Remaining Term (In Years)		3 years 1 month 6 days		2 years 2 months 12 days	1 year 1 month 6 days
2011 Plan \| Years \| Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock granted (in shares)		8,530		2,027
Remaining Term (In Years)		1 month		2 months
2011 Plan \| Three Years [Member] \| Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting Term (In Years)		3 years		3 years
1995 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted in 1995 (in shares)			600,000
Summary of status and changes of Stock Option Plan [Roll Forward]
Granted(in shares)			600,000
Plan 2010 \| One Year \| Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock granted (in shares)	5,086
Remaining Term (In Years)	1 month
Plan 2010 \| Two Years \| Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock granted (in shares)	10,335
Remaining Term (In Years)	1 year
Plan 2010 \| Five Years \| Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock granted (in shares)	10,422
Remaining Term (In Years)	4 years