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Amount of deferred tax expense from write-off of the deferred tax asset related to deductible stock options at exercise.

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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 cash inflow associated with the amount received from holders exercising their stock options. This item inherently excludes any excess tax benefit, which the entity may have realized and reported separately.

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The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

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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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Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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Number of options or other stock instruments for which the right to exercise has lapsed under the terms of the plan agreements.

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

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The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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

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Weighted average price at which grantees could have acquired the underlying shares with respect to stock options of the plan that expired.

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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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Weighted average exercise price as of the balance sheet date for those equity-based payment arrangements exercisable and outstanding.

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

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The floor of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range.

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The number of shares reserved for issuance pertaining to the outstanding exercisable stock options as of the balance sheet date in the customized range of exercise prices for which the market and performance vesting condition has been satisfied.

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The weighted average price as of the balance sheet date at which grantees could acquire the underlying shares with respect to all outstanding stock options which are in the customized range of exercise prices.

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

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The ceiling of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range.

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

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STOCK COMPENSATION PLANS (Details) (USD $)	12 Months Ended
STOCK COMPENSATION PLANS (Details) (USD $)	Dec. 31, 2014 Director	Dec. 31, 2013	Dec. 31, 2012	May 25, 2005
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorizes under the plan (in shares)				500,000
Number of directors consists in committee	3
Weighted Average Exercise [Abstract]
Fair value of options granted (in dollars per shares)	$ 3.95	$ 4.04	$ 2.92
Total intrinsic value of options exercised	$ 247,000	$ 367,000	$ 449,000
Received cash from the exercise of options	732,227
Tax benefit realized during the period	98,344
Options Exercisable [Abstract]
Unrecognized expense related to non-vested option shares	46,000
Period over which unvested options cost will recognized	0 years 4 months 2 days
$15.26 - $19.31 [Member] \| Employee and director [Member]
Options Outstanding [Abstract]
Range of Exercise Price, Minimum (in dollars per shares)	$ 15.26
Range of Exercise Price, Maximum (in dollars per shares)	$ 19.63
Shares Outstanding (in shares)	195,750
Weighted Average Remaining Life	4 years 11 months 16 days
Weighted Average Exercise Price (in dollars per shares)	$ 18.28
Aggregate Intrinsic Value	843,939
Options Exercisable [Abstract]
Range of Exercise Price, Minimum (in dollars per shares)	$ 15.26
Range of Exercise Price, Maximum (in dollars per shares)	$ 19.63
Shares Exercisable (in shares)	195,750
Weighted Average Remaining Life	4 years 11 months 16 days
Weighted Average Exercise Price (in dollars per shares)	$ 18.28
Aggregate Intrinsic Value	843,939
$19.32 - $22.66 [Member] \| Employee and director [Member]
Options Outstanding [Abstract]
Range of Exercise Price, Minimum (in dollars per shares)	$ 19.64
Range of Exercise Price, Maximum (in dollars per shares)	$ 22.66
Shares Outstanding (in shares)	180,500
Weighted Average Remaining Life	3 years 11 months 19 days
Weighted Average Exercise Price (in dollars per shares)	$ 20.89
Aggregate Intrinsic Value	313,057
Options Exercisable [Abstract]
Range of Exercise Price, Minimum (in dollars per shares)	$ 19.64
Range of Exercise Price, Maximum (in dollars per shares)	$ 22.66
Shares Exercisable (in shares)	146,750
Weighted Average Remaining Life	2 years 8 months 26 days
Weighted Average Exercise Price (in dollars per shares)	$ 20.64
Aggregate Intrinsic Value	$ 288,419
Class A Stock [Member] \| Stock Options [Member]
Shares [Abstract]
Outstanding at beginning of year (in shares)	387,000	421,500	450,000
Granted (in shares)	33,750	33,750	33,750
Exercised (in shares)	(44,500)	(68,250)	(62,250)
Expired (in shares)	0	0	0
Outstanding at end of year (in shares)	376,250	387,000	421,500
Options exercisable at year end (in shares)	342,500	353,250	387,750
Weighted Average Exercise [Abstract]
Outstanding at beginning of year (in dollars per shares)	$ 18.96	$ 18.30	$ 17.61
Granted (in dollars per shares)	$ 21.86	$ 22.66	$ 19.01
Exercised (in dollars per shares)	$ 16.45	$ 16.68	$ 13.68
Expired (in dollars per shares)	$ 0	$ 0	$ 0
Outstanding at end of year (in dollars per shares)	$ 19.52	$ 18.96	$ 18.30
Options exercisable at year end (in dollars per shares)	$ 19.29	$ 18.61	$ 18.24