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STOCK COMPENSATION PLANS (Details) |  | 12 Months Ended |
--- | --- | --- | ---
Dec. 18, 2015 $ / shares shares | Dec. 31, 2015 USD ($) Director $ / shares shares | Dec. 31, 2014 USD ($) $ / shares shares | Dec. 31, 2013 USD ($) $ / shares shares | Dec. 09, 2015 shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Number of shares authorizes under the plan (in shares) | shares |  |  |  |  | 331,500
Shares issued as fully vested unrestricted stock awards | shares | 5,000 |  |  |  |
Fair market value | $ 27.38 |  |  |  |
Number of directors in committee | Director |  | 3 |  |  |
Weighted Average Exercise [Abstract] |  |  |  |  |
Fair value of options granted (in dollars per shares) |  | $ 3.95 | $ 4.04 |  |
Total intrinsic value of options exercised | $ |  | $ 379,000 | $ 247,000 | $ 367,000 |
Received cash from the exercise of options | $ |  | 2,100,000 |  |  |
Tax benefit realized during the period | $ |  | $ 379,000 |  |  |
$15.26 - $19.04 [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) |  | $ 19.04 |  |  |
Shares Outstanding (in shares) | shares |  | 135,000 |  |  |
Weighted Average Remaining Life |  | 4 years 1 month 13 days |  |  |
Weighted Average Exercise Price (in dollars per shares) |  | $ 17.83 |  |  |
Aggregate Intrinsic Value | $ |  | $ 1,332,788 |  |  |
Options Exercisable [Abstract] |  |  |  |  |
Range of Exercise Price, Minimum (in dollars per shares) |  | $ 15.26 |  |  |
Range of Exercise Price, Maximum (in dollars per shares) |  | $ 19.04 |  |  |
Shares Exercisable (in shares) | shares |  | 135,000 |  |  |
Weighted Average Remaining Life |  | 4 years 1 month 13 days |  |  |
Weighted Average Exercise Price (in dollars per shares) |  | $ 17.83 |  |  |
Aggregate Intrinsic Value | $ |  | $ 1,332,788 |  |  |
$19.05 - $22.66 [Member] | Employee and director [Member] |  |  |  |  |
Options Outstanding [Abstract] |  |  |  |  |
Range of Exercise Price, Minimum (in dollars per shares) |  | $ 19.05 |  |  |
Range of Exercise Price, Maximum (in dollars per shares) |  | $ 22.66 |  |  |
Shares Outstanding (in shares) | shares |  | 135,000 |  |  |
Weighted Average Remaining Life |  | 5 years 6 months 22 days |  |  |
Weighted Average Exercise Price (in dollars per shares) |  | $ 20.87 |  |  |
Aggregate Intrinsic Value | $ |  | $ 923,096 |  |  |
Options Exercisable [Abstract] |  |  |  |  |
Range of Exercise Price, Minimum (in dollars per shares) |  | $ 19.05 |  |  |
Range of Exercise Price, Maximum (in dollars per shares) |  | $ 22.66 |  |  |
Shares Exercisable (in shares) | shares |  | 135,000 |  |  |
Weighted Average Remaining Life |  | 5 years 6 months 22 days |  |  |
Weighted Average Exercise Price (in dollars per shares) |  | $ 20.86 |  |  |
Aggregate Intrinsic Value | $ |  | $ 923,096 |  |  |
Class A Stock [Member] | Stock Options [Member] |  |  |  |  |
Shares [Abstract] |  |  |  |  |
Outstanding at beginning of year (in shares) | shares |  | 376,250 | 387,000 | 421,500 |
Granted (in shares) | shares |  | 0 | 33,750 | 33,750 |
Exercised (in shares) | shares |  | (106,250) | (44,500) | (68,250) |
Expired (in shares) | shares |  | 0 | 0 | 0 |
Outstanding at end of year (in shares) | shares |  | 270,000 | 376,250 | 387,000 |
Options exercisable at year end (in shares) | shares |  | 270,000 | 342,500 | 353,250 |
Weighted Average Exercise [Abstract] |  |  |  |  |
Outstanding at beginning of year (in dollars per shares) |  | $ 19.52 | $ 18.96 | $ 18.30 |
Granted (in dollars per shares) |  | 0 | 21.86 | 22.66 |
Exercised (in dollars per shares) |  | 19.97 | 16.45 | 16.68 |
Expired (in dollars per shares) |  | 0 | 0 | 0 |
Outstanding at end of year (in dollars per shares) |  | 19.34 | 19.52 | 18.96 |
Options exercisable at year end (in dollars per shares) |  | $ 19.34 | $ 19.29 | $ 18.61 |

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