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STOCK COMPENSATION PLANS (Details) |  |  |  |  | 12 Months Ended
--- | --- | --- | --- | --- | ---
Jun. 28, 2017 $ / shares shares | May 03, 2017 $ / shares shares | May 04, 2016 $ / shares shares | Dec. 18, 2015 $ / shares shares | Dec. 31, 2017 USD ($) Director $ / shares shares | Dec. 31, 2016 USD ($) $ / shares shares | Dec. 31, 2015 USD ($) $ / shares shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |
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 | $ |  |  |  |  | $ 1,198,000 | $ 351,000 | $ 379,000
Received cash from the exercise of options | $ |  |  |  |  | 957,000 |  |
Tax benefit realized during the period | $ |  |  |  |  | 1,400,000 |  |
Options Exercisable [Abstract] |  |  |  |  |  |  |
Unrecognized expense related to non-vested option shares | $ |  |  |  |  | 64,000 |  |
Shares [Roll Forward] |  |  |  |  |  |  |
Granted (in shares) | shares |  |  | 5,000 |  |  |  |
Weighted Average Exercise Price [Abstract] |  |  |  |  |  |  |
Fair market value (in dollars per share) |  |  | $ 27.70 |  |  |  |
Award vesting period |  |  | 1 year |  |  |  |
Intrinsic value of awards | $ |  |  |  |  | $ 441,000 |  |
$15.26 - $18.61 [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) |  |  |  |  | $ 18.61 |  |
Shares Outstanding (in shares) | shares |  |  |  |  | 41,802 |  |
Weighted Average Remaining Life |  |  |  |  | 1 year 11 months 26 days |  |
Weighted Average Exercise Price (in dollars per shares) |  |  |  |  | $ 17.52 |  |
Aggregate Intrinsic Value | $ |  |  |  |  | $ 879,409 |  |
Options Exercisable [Abstract] |  |  |  |  |  |  |
Range of Exercise Price, Minimum (in dollars per shares) |  |  |  |  | $ 15.26 |  |
Range of Exercise Price, Maximum (in dollars per shares) |  |  |  |  | $ 18.61 |  |
Shares Exercisable (in shares) | shares |  |  |  |  | 41,802 |  |
Weighted Average Remaining Life |  |  |  |  | 1 year 11 months 26 days |  |
Weighted Average Exercise Price (in dollars per shares) |  |  |  |  | $ 17.52 |  |
Aggregate Intrinsic Value | $ |  |  |  |  | $ 879,409 |  |
$18.62 - $22.66 [Member] | Employee and Director [Member] |  |  |  |  |  |  |
Options Outstanding [Abstract] |  |  |  |  |  |  |
Range of Exercise Price, Minimum (in dollars per shares) |  |  |  |  | $ 18.62 |  |
Range of Exercise Price, Maximum (in dollars per shares) |  |  |  |  | $ 22.66 |  |
Shares Outstanding (in shares) | shares |  |  |  |  | 135,000 |  |
Weighted Average Remaining Life |  |  |  |  | 4 years 10 months 10 days |  |
Weighted Average Exercise Price (in dollars per shares) |  |  |  |  | $ 20.64 |  |
Aggregate Intrinsic Value | $ |  |  |  |  | $ 2,418,187 |  |
Options Exercisable [Abstract] |  |  |  |  |  |  |
Range of Exercise Price, Minimum (in dollars per shares) |  |  |  |  | $ 18.62 |  |
Range of Exercise Price, Maximum (in dollars per shares) |  |  |  |  | $ 22.66 |  |
Shares Exercisable (in shares) | shares |  |  |  |  | 135,000 |  |
Weighted Average Remaining Life |  |  |  |  | 4 years 10 months 10 days |  |
Weighted Average Exercise Price (in dollars per shares) |  |  |  |  | $ 20.64 |  |
Aggregate Intrinsic Value | $ |  |  |  |  | $ 2,418,187 |  |
Non-vested Option [Member] |  |  |  |  |  |  |
Options Exercisable [Abstract] |  |  |  |  |  |  |
Unrecognized expense related to non-vested option shares | $ |  |  |  |  | 0 |  |
Restricted Stock Awards [Member] | 2015 Equity Compensation Plan [Member] |  |  |  |  |  |  |
Options Exercisable [Abstract] |  |  |  |  |  |  |
Unrecognized expense related to non-vested option shares | $ |  |  |  |  | $ 63,700 |  |
Weighted Average Exercise Price [Abstract] |  |  |  |  |  |  |
Award vesting period |  |  |  |  | 3 months 29 days |  |
Unrestricted Stock Awards [Member] | 2015 Equity Compensation Plan [Member] |  |  |  |  |  |  |
Weighted Average Exercise Price [Abstract] |  |  |  |  |  |  |
Shares issued as fully vested unrestricted stock awards (in shares) | shares |  |  |  | 5,000 |  |  |
Fair market value (in dollars per share) |  |  |  | $ 27.38 |  |  |
Class A Stock [Member] | Stock Options [Member] |  |  |  |  |  |  |
Shares [Abstract] |  |  |  |  |  |  |
Outstanding at beginning of year (in shares) | shares |  |  |  |  | 231,755 | 270,000 | 376,250
Granted (in shares) | shares |  |  |  |  | 0 | 0 | 0
Exercised (in shares) | shares |  |  |  |  | (54,953) | (38,245) | (106,250)
Expired (in shares) | shares |  |  |  |  | 0 | 0 | 0
Outstanding at end of year (in shares) | shares |  |  |  |  | 176,802 | 231,755 | 270,000
Options exercisable at year end (in shares) | shares |  |  |  |  | 176,802 | 231,755 | 270,000
Weighted Average Exercise [Abstract] |  |  |  |  |  |  |
Outstanding at beginning of year (in dollars per shares) |  |  |  |  | $ 19.32 | $ 19.34 | $ 19.52
Granted, weighted average exercise price (in dollars per share) |  |  |  |  | 0 | 0 | 0
Exercised, weighted average exercise price (in dollars per shares) |  |  |  |  | 17.42 | 19.50 | 19.97
Expired, weighted average exercise price (in dollars per share) |  |  |  |  | 0 | 0 | 0
Outstanding at end of year (in dollars per shares) |  |  |  |  | 19.91 | 19.32 | 19.34
Options exercisable at year end (in dollars per shares) |  |  |  |  | $ 19.91 | $ 19.32 | $ 19.34
Class A Stock [Member] | Restricted Stock Awards [Member] |  |  |  |  |  |  |
Shares [Roll Forward] |  |  |  |  |  |  |
Outstanding at beginning of year (in shares) | shares |  |  |  |  | 5,000 | 0 | 0
Granted (in shares) | shares |  |  |  |  | 11,568 | 5,000 | 5,000
Vested/Released (in shares) | shares |  |  |  |  | (11,568) | 0 | (5,000)
Cancelled (in shares) | shares |  |  |  |  | 0 | 0 | 0
Unvested Outstanding at end of year (in shares) | shares |  |  |  |  | 5,000 | 5,000 | 0
Weighted Average Grant Date Fair Value [Abstract] |  |  |  |  |  |  |
Outstanding at beginning of year (in dollars per shares) |  |  |  |  | $ 27.70 | $ 0 |
Granted (in dollars per shares) |  |  |  |  | 38.08 | 27.70 |
Vested/Released (in dollars per shares) |  |  |  |  | 33.58 | 0 |
Cancelled (in dollars per shares) |  |  |  |  | 0 | 0 |
Unvested Outstanding at end of year (in dollars per shares) |  |  |  |  | $ 38.10 | 27.70 | $ 0
Weighted Average Exercise Price [Abstract] |  |  |  |  |  |  |
Outstanding at beginning of year (in dollars per shares) |  |  |  |  |  | $ 0 | 0
Granted (in dollars per shares) |  |  |  |  |  |  | 27.38
Vested/Released (in dollars per shares) |  |  |  |  |  |  | 27.38
Cancelled (in dollars per shares) |  |  |  |  |  |  | 0
Unvested Outstanding at end of year (in dollars per shares) |  |  |  |  |  |  | $ 0
Class A Stock [Member] | Restricted Stock Awards [Member] | 2015 Equity Compensation Plan [Member] |  |  |  |  |  |  |
Shares [Roll Forward] |  |  |  |  |  |  |
Granted (in shares) | shares | 6,568 | 5,000 | 5,000 |  |  |  |
Weighted Average Exercise Price [Abstract] |  |  |  |  |  |  |
Fair market value (in dollars per share) | $ 38.06 | $ 38.10 | $ 27.70 |  |  |  |
Award vesting period |  | 1 year | 1 year |  |  |  |
Class A Stock [Member] | Unrestricted Stock Awards [Member] | 2015 Equity Compensation Plan [Member] |  |  |  |  |  |  |
Shares [Roll Forward] |  |  |  |  |  |  |
Granted (in shares) | shares | 6,568 |  |  |  |  |  |
Weighted Average Exercise Price [Abstract] |  |  |  |  |  |  |
Fair market value (in dollars per share) | $ 38.06 |  |  |  |  |  |

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- Definition Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(2)(iii)(3) -URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901 + Details
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- Definition 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). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(2)(iii)(1) -URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901 + Details
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- Definition The weighted average fair value at grant date for nonvested equity-based awards issued 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). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(2)(iii)(1) -URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901 + Details
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- Definition The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(2)(i)-(ii) -URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901 + Details
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- Definition The weighted average fair value of nonvested awards on equity-based plans excluding option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, revenue or profit achievement stock award plan) for which the employer is contingently obligated to issue equity instruments or transfer assets to an employee who has not yet satisfied service or performance criteria necessary to gain title to proceeds from the sale of the award or underlying shares or units. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(2)(i)-(ii) -URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901 + Details
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- Definition The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(2)(iii)(2) -URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901 + Details
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- Definition The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(2)(iii)(2) -URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901 + Details
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- Definition 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. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(1)(iii) -URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901 + Details
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- Definition 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. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(1)(iii) -URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901 + Details
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- Definition 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. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (d)(2) -URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901 + Details
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- Definition Number of options or other stock instruments for which the right to exercise has lapsed under the terms of the plan agreements. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(1)(iv)(4) -URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901 + Details
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- Definition Gross number of share options (or share units) granted during the period. + References No definition available. + Details
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- Definition Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901 + Details
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- Definition Number of options outstanding, including both vested and non-vested options. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(1)(i)-(ii) -URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901 + Details
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