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STOCK COMPENSATION PLANS (Details) |  |  |  | 12 Months Ended
--- | --- | --- | --- | ---
May 06, 2020 $ / shares shares | May 08, 2019 $ / shares shares | May 02, 2018 $ / shares shares | Dec. 31, 2020 USD ($) Director $ / shares shares | Dec. 31, 2019 USD ($) $ / shares shares | Dec. 31, 2018 USD ($) $ / shares shares
Stock Compensation Plans [Abstract] |  |  |  |  |  |
Number of directors in committee | Director |  |  |  | 3 |  |
Shares [Abstract] |  |  |  |  |  |
Granted (in shares) | shares |  |  |  | 0 | 0 | 0
Weighted Average Exercise [Abstract] |  |  |  |  |  |
Total intrinsic value of options exercised | $ |  |  |  | $ 620,000 | $ 334,000 | $ 176,000
Received cash from the exercise of options | $ |  |  |  | 695,000 |  |
Tax benefit realized during the period | $ |  |  |  | 799,000 |  |
Unrecognized expense related to non-vested option shares | $ |  |  |  | 59,900 |  |
Weighted Average Exercise Price [Abstract] |  |  |  |  |  |
Intrinsic value of awards | $ |  |  |  | $ 178,250 |  |
$19.01 - $20.46 [Member] | Employee and Director [Member] |  |  |  |  |  |
Options Outstanding [Abstract] |  |  |  |  |  |
Range of Exercise Price, Minimum (in dollars per shares) |  |  |  | $ 19.01 |  |
Range of Exercise Price, Maximum (in dollars per shares) |  |  |  | $ 20.46 |  |
Shares Outstanding (in shares) | shares |  |  |  | 48,847 |  |
Weighted Average Remaining Life |  |  |  | 11 months 1 day |  |
Weighted Average Exercise Price (in dollars per shares) |  |  |  | $ 19.03 |  |
Aggregate Intrinsic Value | $ |  |  |  | $ 881,573 |  |
Options Exercisable [Abstract] |  |  |  |  |  |
Range of Exercise Price, Minimum (in dollars per shares) |  |  |  | $ 19.01 |  |
Range of Exercise Price, Maximum (in dollars per shares) |  |  |  | 20.46 |  |
$20.47 - $22.66 [Member] | Employee and Director [Member] |  |  |  |  |  |
Options Outstanding [Abstract] |  |  |  |  |  |
Range of Exercise Price, Minimum (in dollars per shares) |  |  |  | 20.47 |  |
Range of Exercise Price, Maximum (in dollars per shares) |  |  |  | $ 22.66 |  |
Shares Outstanding (in shares) | shares |  |  |  | 67,500 |  |
Weighted Average Remaining Life |  |  |  | 2 years 10 months 6 days |  |
Weighted Average Exercise Price (in dollars per shares) |  |  |  | $ 22.26 |  |
Aggregate Intrinsic Value | $ |  |  |  | $ 1,000,350 |  |
Options Exercisable [Abstract] |  |  |  |  |  |
Range of Exercise Price, Minimum (in dollars per shares) |  |  |  | $ 20.47 |  |
Range of Exercise Price, Maximum (in dollars per shares) |  |  |  | $ 22.66 |  |
Non-vested Option [Member] |  |  |  |  |  |
Weighted Average Exercise [Abstract] |  |  |  |  |  |
Unrecognized expense related to non-vested option shares | $ |  |  |  | $ 0 |  |
Restricted Stock Awards [Member] | 2015 Equity Compensation Plan [Member] |  |  |  |  |  |
Weighted Average Exercise [Abstract] |  |  |  |  |  |
Unrecognized expense related to non-vested option shares | $ |  |  |  | $ 59,900 |  |
Weighted Average Exercise Price [Abstract] |  |  |  |  |  |
Award vesting period |  |  |  | 4 months 6 days |  |
Class A Stock [Member] | Stock Options [Member] |  |  |  |  |  |
Shares [Abstract] |  |  |  |  |  |
Outstanding at beginning of year (in shares) | shares |  |  |  | 153,250 | 168,750 | 176,802
Granted (in shares) | shares |  |  |  | 0 | 0 | 0
Exercised/vested and released, option shares (in shares) | shares |  |  |  | (36,903) | (15,500) | (8,052)
Expired (in shares) | shares |  |  |  | 0 | 0 | 0
Outstanding at end of year (in shares) | shares |  |  |  | 116,347 | 153,250 | 168,750
Options exercisable at year end (in shares) | shares |  |  |  | 116,347 | 153,250 | 168,750
Weighted Average Exercise [Abstract] |  |  |  |  |  |
Outstanding at beginning of year (in dollars per shares) |  |  |  | $ 20.40 | $ 20.11 | $ 19.91
Granted, weighted average exercise price (in dollars per share) |  |  |  | 0 | 0 | 0
Exercised/vested and released, weighted average exercise price (in dollars per shares) |  |  |  | 18.83 | 17.15 | 15.77
Expired/cancelled, weighted average exercise price (in dollars per share) |  |  |  | 0 | 0 | 0
Outstanding at end of year (in dollars per shares) |  |  |  | 20.90 | 20.40 | 20.11
Options exercisable at year end (in dollars per shares) |  |  |  | $ 20.90 | $ 20.40 | $ 20.11
Class A Stock [Member] | Restricted Stock Awards [Member] |  |  |  |  |  |
Shares [Roll Forward] |  |  |  |  |  |
Outstanding at beginning of year (in shares) | shares |  |  |  | 5,000 | 5,000 | 5,000
Granted (in shares) | shares | 5,000 | 5,000 | 5,000 | 5,000 | 5,000 | 5,000
Vested/Released (in shares) | shares |  |  |  | (5,000) | (5,000) | (5,000)
Cancelled (in shares) | shares |  |  |  | 0 | 0 | 0
Unvested Outstanding at end of year (in shares) | shares |  |  |  | 5,000 | 5,000 | 5,000
Weighted Average Grant Date Fair Value [Abstract] |  |  |  |  |  |
Outstanding at beginning of year (in dollars per shares) |  |  |  | $ 36.11 | $ 38.51 |
Granted (in dollars per shares) |  |  |  | 35.01 | 36.11 |
Vested/Released (in dollars per shares) |  |  |  | 36.11 | 38.51 |
Cancelled (in dollars per shares) |  |  |  | 0 | 0 |
Unvested Outstanding at end of year (in dollars per shares) |  |  |  | $ 35.01 | 36.11 | $ 38.51
Weighted Average Exercise Price [Abstract] |  |  |  |  |  |
Outstanding at beginning of year (in dollars per shares) |  |  |  |  | $ 38.51 | 38.10
Granted (in dollars per shares) |  |  |  |  |  | 38.51
Vested/Released (in dollars per shares) |  |  |  |  |  | 38.10
Cancelled (in dollars per shares) |  |  |  |  |  | 0
Unvested Outstanding at end of year (in dollars per shares) |  |  |  |  |  | $ 38.51
Fair market value (in dollars per share) | $ 35.01 | $ 36.11 | $ 38.51 |  |  |

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- Definition 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. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (g) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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