STOCK-BASED COMPENSATION - Schedule of Non-Vested Stock and Restricted Stock Units (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
Dec. 26, 2020	Dec. 28, 2019	Dec. 29, 2018
Share-based Payment Arrangement, Option
Stock Based Compensation
Compensation expense	$ 14,874	$ 11,587	$ 10,392
Weighted-average period for grant of stock-based compensation	2 years 4 months 20 days
Deferred stock-based compensation granted	$ 5,364
Directors and certain management employees \| Non-vested stock and restricted stock units
Stock Based Compensation
Shares granted	85,251	78,318	88,127
Weighted‑average per share price on grant date	$ 161.73	$ 145.89	$ 114.89
Compensation expense	$ 9,081	$ 8,815	$ 6,328
Weighted-average period for grant of stock-based compensation	2 years 7 months 28 days
Deferred stock-based compensation granted	$ 22,862

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

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