SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Earnings Per Share (Details) - shares	3 Months Ended
Apr. 01, 2018	Mar. 26, 2017
Schedule of Weighted Average Number of Shares, Diluted [Line Items]
Basic (shares)	8,761,292	8,668,955
Effect of dilutive securities:
Weighted-average number of diluted common shares outstanding	9,087,016	8,924,419
Antidilutive securities excluded from computation of earnings per share, amount	210,250	82,250
Employee Stock Option
Effect of dilutive securities:
Stock options	286,875	227,214
Antidilutive securities excluded from computation of earnings per share, amount	178,000	50,000
Warrant
Effect of dilutive securities:
Warrants	38,849	28,250
Antidilutive securities excluded from computation of earnings per share, amount	32,250	32,250

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 45
-Paragraph 23
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=96947427&loc=d3e1757-109256

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 50
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-URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
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-Section 50
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