STOCK-BASED COMPENSATION (Details 3) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
Dec. 28, 2019	Dec. 29, 2018	Dec. 30, 2017
Share-based Payment Arrangement, Option
Stock Based Compensation
Compensation expense	$ 11,587	$ 10,392	$ 10,706
Weighted-average period for grant of stock-based compensation	2 years 3 months 21 days
Deferred stock-based compensation granted	$ 4,979
Directors and certain management employees \| Non-vested stock and restricted stock units
Stock Based Compensation
Shares granted	78,318	88,127	62,160
Weighted‑average per share price on grant date	$ 145.89	$ 114.89	$ 163.18
Compensation expense	$ 8,815	$ 6,328	$ 5,569
Weighted-average period for grant of stock-based compensation	1 year 8 months 12 days
Deferred stock-based compensation granted	$ 19,501

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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