ACCUMULATED OTHER COMPREHENSIVE LOSS (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jul. 01, 2018	Jul. 02, 2017	Jul. 01, 2018	Jul. 02, 2017
Accumulated Other Comprehensive Loss, Net of Tax [Roll Forward]
Balance at beginning of period	$ (9,713)	$ (8,896)	$ (6,804)	$ (11,433)
Cumulative Effect on Retained Earnings, Net of Tax			(1,525)	0
Total other comprehensive income (loss), net of tax	(1,921)	449	(3,305)	2,986
Balance at end of period	(11,634)	(8,447)	(11,634)	(8,447)
Foreign currency translation adjustment
Accumulated Other Comprehensive Loss, Net of Tax [Roll Forward]
Balance at beginning of period	(9,713)	(9,884)	(8,329)	(11,684)
Foreign currency translation adjustment, net of tax	(1,921)	540	(3,305)	2,340
Cumulative Effect on Retained Earnings, Net of Tax			0	0
Balance at end of period	(11,634)	(9,344)	(11,634)	(9,344)
Unrealized gain (loss) on marketable securities
Accumulated Other Comprehensive Loss, Net of Tax [Roll Forward]
Balance at beginning of period	0	988	1,525	251
Unrealized gain (loss) on investments, net of tax	0	(91)	0	646
Cumulative Effect on Retained Earnings, Net of Tax			(1,525)	0
Balance at end of period	$ 0	$ 897	$ 0	$ 897

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

No definition available.

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Accumulated change in equity from transactions and other events and circumstances from non-owner sources, net of tax effect, at period end. Excludes Net Income (Loss), and accumulated changes in equity from transactions resulting from investments by owners and distributions to owners. Includes foreign currency translation items, certain pension adjustments, unrealized gains and losses on certain investments in debt and equity securities, other than temporary impairment (OTTI) losses related to factors other than credit losses on available-for-sale and held-to-maturity debt securities that an entity does not intend to sell and it is not more likely than not that the entity will be required to sell before recovery of the amortized cost basis, as well as changes in the fair value of derivatives related to the effective portion of a designated cash flow hedge.

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Amount of the cumulative effect on retained earnings net of related income tax effect.

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Amount after tax, before reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature.

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Amount after tax and reclassification adjustments of other comprehensive income (loss).

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Amount after tax, before reclassification adjustments, of unrealized holding gain (loss) on available-for-sale securities.

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