ACQUISITIONS (Supplemental Unaudited Pro Forma Information) (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	9 Months Ended
Sep. 27, 2020	Sep. 29, 2019	Sep. 27, 2020	Sep. 29, 2019
Income (Loss) per share:
Effective income tax rate reconciliation, percent	22.00%	24.10%	25.40%	23.30%
L.J. Kushner & Associates, L.L.C.
Business Acquisition [Line Items]
Revenues	$ 71,519	$ 90,334	$ 211,301	$ 254,877
Gross profit	19,712	26,143	57,801	73,466
Net income (loss)	$ 2,566	$ 4,720	$ (952)	$ 12,184
Income (Loss) per share:
Basic pro forma (in usd per share)	$ 0.25	$ 0.46	$ (0.09)	$ 1.19
Diluted pro forma (in usd per share)	$ 0.25	$ 0.46	$ (0.09)	$ 1.18
Pro Forma
Income (Loss) per share:
Effective income tax rate reconciliation, percent	22.00%
Pro Forma \| Revolving Credit Facility
Income (Loss) per share:
Line of credit facility, interest rate during period			2.30%

Business Acquisition, Pro Forma Gross Profit

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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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The pro forma net Income or Loss for the period as if the business combination or combinations had been completed at the beginning of a period.

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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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