INCOME TAXES (Details) - USD ($) $ in Thousands			12 Months Ended
Dec. 22, 2017	Dec. 21, 2017	Dec. 28, 2019	Dec. 29, 2018	Dec. 30, 2017
Income Tax Disclosure [Abstract]
Corporate income tax rate	21.00%	35.00%	21.00%	21.00%	35.00%
Amount from income tax rate reconciliation			$ 0	$ 0	$ 5,737
Components of income before income taxes
Domestic			65,469	69,209	31,927
Foreign			1,789	406	132
Income before income taxes			$ 67,258	$ 69,615	$ 32,059

Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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The portion of earnings or loss from continuing operations before income taxes that is attributable to domestic operations.

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The portion of earnings or loss from continuing operations before income taxes that is attributable to foreign operations, which is defined as Income or Loss generated from operations located outside the entity's country of domicile.

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Amount of income (loss) from continuing operations before deduction of income tax expense (benefit) and income (loss) attributable to noncontrolling interest, and addition of income (loss) from equity method investments.

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Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations, attributable to increase (decrease) in the income tax rates.

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