ACQUISITIONS (Supplemental Unaudited Pro Forma Information) (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
Apr. 01, 2018	Mar. 26, 2017
Zycron, Inc.
Business Acquisition [Line Items]
Revenues		$ 69,389
Gross profit		16,807
Net income		$ 1,481
Income per share:
Basic pro forma (in usd per share)		$ 0.17
Diluted pro forma (in usd per share)		$ 0.17
Pro Forma
Income per share:
Effective income tax rate reconciliation, percent		38.30%
Pro Forma \| Revolving Credit Facility
Income per share:
Line of credit facility, interest rate during period	4.50%

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The pro forma basic net income per share for a period as if the business combination or combinations had been completed at the beginning of a period.

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-Publisher FASB
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Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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