STOCK-BASED COMPENSATION (Details 3) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
Dec. 29, 2018	Dec. 30, 2017	Dec. 31, 2016
Employee Stock Option [Member]
Stock Based Compensation
Compensation expense	$ 4,064	$ 5,137	$ 5,782
Weighted-average period for grant of stock-based compensation	2 years 5 months 9 days
Deferred stock-based compensation granted	$ 5,940
Directors and certain management employees \| Non-vested stock and restricted stock units
Stock Based Compensation
Shares issued	88,127	62,160	58,961
Weighted average per share price on grant date	$ 114.89	$ 163.18	$ 150.48
Compensation expense	$ 6,328	$ 5,569	$ 4,069
Weighted-average period for grant of stock-based compensation	1 year 9 months 26 days
Deferred stock-based compensation granted	$ 17,754

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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Unrecognized cost of unvested share-based compensation awards.

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Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The weighted average fair value of nonvested awards on equity-based plans excluding option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, revenue or profit achievement stock award plan) for which the employer is contingently obligated to issue equity instruments or transfer assets to an employee who has not yet satisfied service or performance criteria necessary to gain title to proceeds from the sale of the award or underlying shares or units.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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