SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Earnings Per Share (Details) - shares	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jul. 01, 2018	Jun. 30, 2019	Jul. 01, 2018
Schedule of Weighted Average Number of Shares, Diluted [Line Items]
Basic (shares)	10,232,588	9,235,353	10,231,025	8,998,364
Effect of dilutive securities:
Weighted-average number of diluted common shares outstanding	10,362,038	9,538,545	10,380,195	9,301,370
Antidilutive securities excluded from computation of earnings per share, amount	239,750	0	239,750	163,600
Stock options and restricted stock
Effect of dilutive securities:
Stock options and restricted stock	89,833	256,414	105,156	261,960
Antidilutive securities excluded from computation of earnings per share, amount	239,750	0	239,750	163,600
Warrant
Effect of dilutive securities:
Warrants	39,617	46,778	44,014	41,046
Antidilutive securities excluded from computation of earnings per share, amount	0	0	0	0

Schedule of Weighted Average Number of Shares, Diluted [Line Items]

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Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

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Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of call options and warrants using the treasury stock method.

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Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of share based payment arrangements using the treasury stock method.

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The average number of shares or units issued and outstanding that are used in calculating diluted EPS or earnings per unit (EPU), determined based on the timing of issuance of shares or units in the period.

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Number of [basic] shares or units, after adjustment for contingently issuable shares or units and other shares or units not deemed outstanding, determined by relating the portion of time within a reporting period that common shares or units have been outstanding to the total time in that period.

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