FAIR VALUE MEASUREMENTS - Other Income From Available For Sale Securities (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 25, 2020	Mar. 27, 2019
Available-for-sale securities
Unrealized Gain (Loss) on Securities	$ (356)	$ 157
Total	(93)	564
Available-for-sale Securities
Available-for-sale securities
Dividend income	184	392
Interest income	0	0
Realized gain (loss) on sale of investments	79	(14)
Unrealized Gain (Loss) on Securities	(356)	157
Total	$ (93)	$ 535

Amount of realized and unrealized gain (loss) on investment.

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Amount before accretion (amortization) of purchase discount (premium) of interest income on nonoperating securities.

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Amount of unrealized gain (loss) recognized in the income statement on unsold other securities.

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