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SHARE-BASED COMPENSATION- Stock Options and Restricted Stock (Details) - USD ($) |  | 12 Months Ended |  |  |  |
--- | --- | --- | --- | --- | --- | ---
May 31, 2018 | Dec. 29, 2019 | Dec. 30, 2018 | Dec. 31, 2017 | Dec. 27, 2015 | Dec. 29, 2019 | Dec. 30, 2018 | May 16, 2017 | Dec. 31, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |
Capital shares reserved for future issuance |  |  |  |  |  | 838,739 |  |  |
Shares issued, price per share (in dollars per share) | $ 18.00 |  |  |  |  |  |  |  |
Option cancellation agreement |  | $ 0 | $ (3,335,169) | $ 0 |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward] |  |  |  |  |  |  |  |  |
Exercised (in shares) |  | (39,014) | (86,053) | (13,800) |  |  |  |  |
Options exercisable (in shares) |  |  |  |  |  | 313,645 | 238,085 |  |
Common stock, shares outstanding (in shares) |  |  |  |  |  | 10,309,236 | 10,227,247 |  |
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) |  | $ 16.05 | $ 13.96 |  |  | $ 16.05 | $ 13.96 |  |
Options exercisable at ending of period (in dollars per share) (in shares) |  | $ 16.05 | $ 13.96 |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract] |  |  |  |  |  |  |  |  |
Options exercisable, weighted average remaining contractual term |  | 6 years 9 months 18 days | 7 years 2 months 12 days |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Intrinsic Value [Abstract] |  |  |  |  |  |  |  |  |
Options exercisable at beginning of period |  | $ 1,991,000 | $ 1,684,000 |  |  | $ 1,991,000 | $ 1,684,000 |  |
Options exercisable at ending of period |  | 1,991,000 | 1,684,000 |  |  |  |  |  |
Employee Stock Option |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |
Compensation cost related to stock awards |  | $ 1,000,000.0 | $ 1,100,000 | $ 400,000 |  |  |  |  |
Unamortized stock compensation expense |  |  |  |  |  | $ 1,800,000 |  |  |
Unamortized stock compensation expense, recognition period |  | 2 years 8 months 12 days |  |  |  |  |  |  |
Conversion of stock, shares issued (in shares) |  | 16,777 | 49,541 | 5,221 |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions and Methodology [Abstract] |  |  |  |  |  |  |  |  |
Weighted-average fair value of warrants |  | $ 6.12 | $ 12.27 | $ 3.94 |  |  |  |  |
Weighted-average risk-free interest rate |  | 2.30% | 2.70% | 1.80% |  |  |  |  |
Weighted-average dividend yield |  | 118.00% | 104.00% | 100.00% |  |  |  |  |
Weighted-average volatility factor |  | 42.60% | 42.30% | 43.20% |  |  |  |  |
Weighted-average expected life |  | 10 years | 8 years 7 months 6 days | 6 years |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward] |  |  |  |  |  |  |  |  |
Options outstanding at beginning of period (in shares) |  | 526,985 | 765,411 | 678,411 |  |  |  |  |
Granted (in shares) |  | 138,750 | 217,000 | 128,000 |  |  |  |  |
Exercised (in shares) |  | (48,190) | (163,338) | (28,800) |  |  |  |  |
Forfeited / Canceled (in shares) |  | (34,700) | (292,088) | (12,200) |  |  |  |  |
Options outstanding at ending of period (in shares) |  | 582,845 | 526,985 | 765,411 |  |  |  |  |
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) |  | $ 16.49 | $ 10.27 | $ 8.95 |  |  |  |  |
Granted (in dollars per share) |  | 21.49 | 20.73 | 16.76 |  |  |  |  |
Exercised (in dollars per share) |  | 10.25 | 10.47 | 7.71 |  |  |  |  |
Forfeited / Canceled (in dollars per share) |  | 14.39 | 6.71 | 11.00 |  |  |  |  |
Options outstanding at ending of period (in dollars per share) |  | $ 18.32 | $ 16.49 | $ 10.27 |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract] |  |  |  |  |  |  |  |  |
Options outstanding, weighted average remaining contractual term |  | 7 years 6 months | 7 years 8 months 12 days | 7 years 3 months 18 days | 7 years 9 months 18 days |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Intrinsic Value [Abstract] |  |  |  |  |  |  |  |  |
Options outstanding at beginning of period |  | $ 2,932,000 | $ 4,521,000 | $ 4,511,000 |  |  |  |  |
Options outstanding at ending of period |  | 2,793,000 | 2,932,000 | 4,521,000 |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract] |  |  |  |  |  |  |  |  |
Nonvested, number of shares |  |  |  |  |  | 269,200 | 288,900 |  |
Nonvested options, weighted average grant date fair value |  |  |  |  |  | $ 20.96 | $ 8.34 |  |
Restricted Stock |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |
Compensation cost related to stock awards |  | $ 200,000 | $ 400,000 | $ 0 |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward] |  |  |  |  |  |  |  |  |
Common stock, shares outstanding (in shares) |  |  |  |  |  | 18,000 | 31,500 |  |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Abstract] |  |  |  |  |  |  |  |  |
Granted (in dollars per share) |  | $ 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 (in dollars 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 (in shares) | (284,888) |  |  |  |  |  |  |  |

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