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STOCK COMPENSATION PLANS (Details) |  |  |  |  | 3 Months Ended | 6 Months Ended
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May 02, 2018 $ / shares shares | Jun. 28, 2017 $ / shares shares | May 03, 2017 $ / shares shares | May 04, 2016 $ / shares shares | Jun. 30, 2018 USD ($) $ / shares shares | Jun. 30, 2017 USD ($) | Jun. 30, 2018 USD ($) Director $ / shares shares | Jun. 30, 2017 USD ($)
Stock Compensation Plans [Abstract] |  |  |  |  |  |  |  |
Number of directors in committee | Director |  |  |  |  |  |  | 3 |
Class A Stock [Member] | Stock Options [Member] |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward] |  |  |  |  |  |  |  |
Outstanding at beginning of period, option shares (in shares) | shares |  |  |  |  |  |  | 176,802 |
Granted, option shares (in shares) | shares |  |  |  |  |  |  | 0 |
Exercised/vested and released, option shares (in shares) | shares |  |  |  |  |  |  | (8,052) |
Expired/cancelled, option shares (in shares) | shares |  |  |  |  |  |  | 0 |
Outstanding at end of period, option shares (in shares) | shares |  |  |  |  | 168,750 |  | 168,750 |
Exercisable/vested at end of period, option share (in shares) | shares |  |  |  |  | 168,750 |  | 168,750 |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Abstract] |  |  |  |  |  |  |  |
Outstanding at beginning of period, weighted average exercise price (in dollars per shares) |  |  |  |  |  |  | $ 19.91 |
Granted, weighted average exercise price (in dollars per share) |  |  |  |  |  |  | 0 |
Exercised/vested and released, weighted average exercise price (in dollars per shares) |  |  |  |  |  |  | 15.77 |
Expired/cancelled, weighted average exercise price (in dollars per share) |  |  |  |  |  |  | 0 |
Outstanding at end of period, weighted average exercise price (in dollars per shares) |  |  |  |  | $ 20.11 |  | 20.11 |
Options exercisable at year end (in dollars per shares) |  |  |  |  | $ 20.11 |  | $ 20.11 |
Shares of Class A Non-Voting Common Stock under option [Abstract] |  |  |  |  |  |  |  |
Outstanding at end of period, weighted average remaining life |  |  |  |  |  |  | 3 years 9 months 29 days |
Exercisable/vested at end of period, weighted average remaining life |  |  |  |  |  |  | 3 years 9 months 29 days |
Outstanding at beginning of period, aggregate intrinsic value | $ |  |  |  |  |  |  | $ 3,298,000 |
Granted, aggregate intrinsic value | $ |  |  |  |  |  |  | 0 |
Exercised/vested and released, aggregate intrinsic value | $ |  |  |  |  |  |  | 176,000 |
Expired/cancelled, aggregate intrinsic value | $ |  |  |  |  |  |  | 0 |
Outstanding at end of period, aggregate intrinsic value | $ |  |  |  |  | $ 3,150,000 |  | 3,150,000 |
Exercisable/vested at end of period, aggregate intrinsic value | $ |  |  |  |  | 3,150,000 |  | 3,150,000 |
Class A Stock [Member] | Stock Options [Member] | 2015 Equity Compensation Plan [Member] |  |  |  |  |  |  |  |
Stock Compensation Plans [Abstract] |  |  |  |  |  |  |  |
Unrecognized expense related to non-vested option shares | $ |  |  |  |  | 0 |  | 0 |
Class A Stock [Member] | Restricted Stock [Member] |  |  |  |  |  |  |  |
Stock Compensation Plans [Abstract] |  |  |  |  |  |  |  |
Compensation expense | $ |  |  |  |  | $ 48,000 | $ 293,000 | $ 95,000 | $ 327,000
Fair value per share (in dollars per share) | $ 38.51 | $ 38.06 | $ 38.10 | $ 27.70 |  |  |  |
Award vesting period |  |  |  |  |  |  | 1 year |
Shares [Roll Forward] |  |  |  |  |  |  |  |
Outstanding at beginning of year (in shares) | shares |  |  |  |  |  |  | 5,000 |
Granted (in shares) | shares | 5,000 | 6,568 | 5,000 | 5,000 |  |  | 5,000 |
Exercised/vested and released, restricted stock awards (in shares) | shares |  |  |  |  |  |  | (5,000) |
Cancelled (in shares) | shares |  |  |  |  |  |  | 0 |
Unvested Outstanding at end of year (in shares) | shares |  |  |  |  | 5,000 |  | 5,000 |
Weighted Average Grant Date Fair Value [Abstract] |  |  |  |  |  |  |  |
Outstanding at beginning of year (in dollars per shares) |  |  |  |  |  |  | $ 38.10 |
Granted, weighted average grant date fair value (in dollars per share) |  |  |  |  |  |  | 38.51 |
Vested and released, weighted average grant date fair value (in dollars per shares) |  |  |  |  |  |  | 38.10 |
Cancelled, weighted average grant date fair value (in dollars per share) |  |  |  |  |  |  | 0 |
Unvested Outstanding at end of year (in dollars per shares) |  |  |  |  | $ 38.51 |  | $ 38.51 |
Class A Stock [Member] | Restricted Stock [Member] | 2015 Equity Compensation Plan [Member] |  |  |  |  |  |  |  |
Stock Compensation Plans [Abstract] |  |  |  |  |  |  |  |
Unrecognized expense related to non-vested option shares | $ |  |  |  |  | $ 160,900 |  | $ 160,900 |
Period over which unvested options cost will recognized |  |  |  |  |  |  | 10 months 2 days |

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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://fasb.org/us-gaap/role/ref/legacyRef -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=109197908&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://fasb.org/us-gaap/role/ref/legacyRef -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=109197908&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://fasb.org/us-gaap/role/ref/legacyRef -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=109197908&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://fasb.org/us-gaap/role/ref/legacyRef -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=109197908&loc=d3e5070-113901 + Details
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- Definition 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. + 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 (e)(1) -URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901 + Details
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