INCOME TAXES - Reconciliation of Income Tax Expense (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 25, 2020	Mar. 27, 2019
Income Tax Disclosure [Abstract]
Expected U.S. federal income taxes at statutory rate	$ (208)	$ 1,188
Expected U.S. federal income taxes at statutory rate, percentage	21.00%	21.00%
State and local income taxes, net of federal benefit	$ (125)	$ 418
State and local income taxes, net of federal benefit, percentage	12.60%	7.40%
Foreign withholding taxes	$ 534	$ 342
Foreign withholding taxes, percentage	(53.80%)	6.00%
Tax credits and adjustments to forecasted rate	$ (34)	$ (376)
Tax credits, percentage	3.40%	(6.60%)
Effective Income Tax Rate Reconciliation, Return To Provision Adjustment, Amount	$ 0	$ 0
Effective Income Tax Rate Reconciliation, Return To Provision Adjustment, Percent	0.00%	0.00%
Non-controlling interest	$ (80)	$ (323)
Non-controlling interest, percentage	8.00%	(5.70%)
Tax effect of change in basis related to ASC 842 adoption	$ 0	$ 1,161
Tax effect of change in basis related to ASC 842 adoption, percent	0.00%	20.50%
Effective Income Tax Rate Reconciliation, Change in Deferred Tax Assets Valuation Allowance, Amount	$ 0	$ (365)
Effective Income Tax Rate Reconciliation, Change in Deferred Tax Assets Valuation Allowance, Percent	0.00%	(6.50%)
Other	$ 0	$ 2
Other, percentage	0.00%	0.10%
Income tax expense	$ 87	$ 2,047
Income tax expense, percentage	(8.80%)	36.20%

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