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SHARE-BASED COMPENSATION- Stock Options and Restricted Stock (Details) - USD ($) |  | 12 Months Ended |  |  |  |  |
--- | --- | --- | --- | --- | --- | --- | ---
May 31, 2018 | Dec. 30, 2018 | Dec. 31, 2017 | Dec. 25, 2016 | Dec. 27, 2015 | Dec. 30, 2018 | May 25, 2018 | Dec. 31, 2017 | May 16, 2017 | Dec. 31, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |
Capital shares reserved for future issuance |  |  |  |  |  | 864,516 |  |  |  |
Shares issued, price per share |  |  |  |  |  |  | $ 18.00 |  |  |
Option cancellation agreement |  | $ (3,335,169) | $ 0 | $ 0 |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward] |  |  |  |  |  |  |  |  |  |
Exercised |  | (86,053) | (13,800) | (87,655) |  |  |  |  |  |
Options exercisable (in shares) |  |  |  |  |  | 238,085 |  | 498,611 |  |
Common Stock, Shares Outstanding |  |  |  |  |  | 10,227,247 |  | 8,759,376 |  |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Abstract] |  |  |  |  |  |  |  |  |  |
Options exercisable at beginning of period (in dollars per share) (in shares) |  | $ 13.96 | $ 8.74 |  |  | $ 13.96 |  | $ 8.74 |  |
Options exercisable at ending of period (in dollars per share) (in shares) |  | $ 13.96 | $ 8.74 |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract] |  |  |  |  |  |  |  |  |  |
Options exercisable, weighted average remaining contractual term |  | 7 years 2 months 12 days | 6 years 9 months 15 days |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Intrinsic Value [Abstract] |  |  |  |  |  |  |  |  |  |
Options exercisable at beginning of period |  | $ 1,684,000 | $ 3,640,000 |  |  | $ 1,684,000 |  | $ 3,640,000 |  |
Options exercisable at ending of period |  | 1,684,000 | 3,640,000 |  |  |  |  |  |  |
Employee Stock Option |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |
Compensation cost related to stock awards |  | $ 1,100,000 | $ 400,000 | $ 300,000 |  |  |  |  |  |
Unamortized stock compensation expense |  |  |  |  |  | $ 1,300,000 |  |  |  |
Unamortized stock compensation expense, recognition period |  | 3 years 2 days |  |  |  |  |  |  |  |
Conversion of stock, shares issued |  | 49,541 | 5,221 | 55,974 |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions and Methodology [Abstract] |  |  |  |  |  |  |  |  |  |
Weighted-average fair value of warrants |  | $ 12.27 | $ 3.94 | $ 4.05 |  |  |  |  |  |
Weighted-average risk-free interest rate |  | 2.70% | 1.80% | 1.10% |  |  |  |  |  |
Weighted-average dividend yield |  | 100.00% | 100.00% | 100.00% |  |  |  |  |  |
Weighted-average volatility factor |  | 42.30% | 43.20% | 43.20% |  |  |  |  |  |
Weighted-average expected life |  | 8 years 7 months 24 days | 6 years | 6 years |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward] |  |  |  |  |  |  |  |  |  |
Options outstanding at beginning of period (in shares) |  | 765,411 | 678,411 | 775,666 |  |  |  |  |  |
Granted |  | 217,000 | 128,000 | 50,000 |  |  |  |  |  |
Exercised |  | (163,338) | (28,800) | (103,055) |  |  |  |  |  |
Forfeited / Canceled |  | (292,088) | (12,200) | (44,200) |  |  |  |  |  |
Options outstanding at ending of period (in shares) |  | 526,985 | 765,411 | 678,411 | 775,666 |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Abstract] |  |  |  |  |  |  |  |  |  |
Options outstanding at beginning of period (in dollars per share) |  | $ 10.27 | $ 8.95 | $ 8.19 |  |  |  |  |  |
Granted |  | 20.73 | 16.76 | 17.46 |  |  |  |  |  |
Exercised |  | 10.47 | 7.71 | 6.91 |  |  |  |  |  |
Forfeited / Canceled |  | 6.71 | 11.00 | 9.94 |  |  |  |  |  |
Options outstanding at ending of period (in dollars per share) |  | $ 16.49 | $ 10.27 | $ 8.95 | $ 8.19 |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract] |  |  |  |  |  |  |  |  |  |
Options outstanding, weighted average remaining contractual term |  | 7 years 8 months 19 days | 7 years 3 months 7 days | 7 years 10 months 6 days | 8 years 8 months 6 days |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Intrinsic Value [Abstract] |  |  |  |  |  |  |  |  |  |
Options outstanding at beginning of period |  | $ 4,521,000 | $ 4,511,000 | $ 5,246,000 |  |  |  |  |  |
Options outstanding at ending of period |  | 2,932,000 | 4,521,000 | 4,511,000 | $ 5,246,000 |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract] |  |  |  |  |  |  |  |  |  |
Nonvested, number of shares |  |  |  |  |  | 288,900 |  | 266,800 |  |
Nonvested options, weighted average grant date fair value |  |  |  |  |  | $ 8.34 |  | $ 3.09 |  |
Restricted Stock |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |
Compensation cost related to stock awards |  | $ 400,000 | $ 0 | $ 0 |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward] |  |  |  |  |  |  |  |  |  |
Common Stock, Shares Outstanding |  |  |  |  |  | 31,500 |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Abstract] |  |  |  |  |  |  |  |  |  |
Granted |  | $ 28.61 |  |  |  |  |  |  |  |
Long Term Incentive Plan 2013 |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |
Capital shares reserved for future issuance |  |  |  |  |  |  |  |  |  | 900,000
Additional capital shares reserved for future issuance |  |  |  |  |  |  |  |  | 250,000 |
Long Term Incentive Plan 2013 | Vested Immediately |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |
Vesting rights, percentage |  | 20.00% |  |  |  |  |  |  |  |
Long Term Incentive Plan 2013 | Vesting Over Four Years |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |
Vesting rights, percentage |  | 20.00% |  |  |  |  |  |  |  |
Long Term Incentive Plan 2013 | Maximum |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |
Expiration period, options (in years) |  | 10 years |  |  |  |  |  |  |  |
Chief Executive Officer | Cancellation Agreement |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |
Shares issued, price per share | $ 18.00 |  |  |  |  |  |  |  |  |
Option cancellation agreement | $ 3,300,000 |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward] |  |  |  |  |  |  |  |  |  |
Forfeited / Canceled | (284,888) |  |  |  |  |  |  |  |  |

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