STOCK-BASED COMPENSATION (Tables)

12 Months Ended

Dec. 30, 2017

Disclosure of Compensation Related Costs, Share-based Payments [Abstract]

Schedule of assumptions used in estimating fair value of each option grant

	2017		2016		2015
Expected volatility	33.76	%	33.88	%	34.13	%
Risk-free interest rate	2.12	%	1.83	%	1.58	%
Expected life from vesting date	3.0 yrs		3.0 yrs		3.0 yrs
Dividend yield	1.17	%	1.13	%	0.94	%

Summary of activity of stock plans

Following is a summary of the activity of the stock plans during 2015, 2016 and 2017:

	Number of Shares		Weighted Average Exercise Price		Weighted Average Remaining Contractual Term	Aggregate Intrinsic Value
Outstanding at December 27, 2014	768,595		$	113.72
Granted	291,708		104.89
Exercised	(169,493	)	74.37
Forfeited	(41,201	)	137.02
Outstanding at December 26, 2015	849,609		$	117.42	5.18	$	4,536
Options vested or expected to vest at December 26, 2015	818,300		$	117.61	5.13	4,456
Options exercisable at December 26, 2015	409,068		$	119.43	3.74	3,376

The weighted average per share fair value of options granted during 2015 was $27.91.

	Number of Shares		Weighted Average Exercise Price		Weighted Average Remaining Contractual Term	Aggregate Intrinsic Value
Outstanding at December 26, 2015	849,609		$	117.42
Granted	85,092		151.37
Exercised	(109,893	)	101.69
Forfeited	(31,635	)	129.36
Outstanding at December 31, 2016	793,173		$	122.77	4.78	$	16,640
Options vested or expected to vest at December 31, 2016	774,139		$	124.18	4.75	16,200
Options exercisable at December 31, 2016	469,844		$	123.75	3.96	9,056

The weighted average per share fair value of options granted during 2016 was $40.00.

	Number of Shares		Weighted Average Exercise Price		Weighted Average Remaining Contractual Term	Aggregate Intrinsic Value
Outstanding at December 31, 2016	793,173		$	122.77
Granted	67,965		164.35
Exercised	(284,574	)	121.92
Forfeited	(5,942	)	104.26
Outstanding at December 30, 2017	570,622		$	128.34	4.66	$	21,806
Options vested or expected to vest at December 30, 2017	558,114		$	128.00	4.63	21,517
Options exercisable at December 30, 2017	351,794		$	123.90	3.94	15,005

The weighted average per share fair value of options granted during 2017 was $43.68.

Summary of status of stock options outstanding

Following is a summary of the status of stock options outstanding at December 30, 2017:

Outstanding and Exercisable By Price Range
Options Outstanding					Options Exercisable
Exercise Price Range	Number	Weighted Average Remaining Contractual Life	Weighted Average Exercise Price		Number	Weighted Average Exercise Price
$83.94 - 114.11	239,480	4.71 years	$	103.23	147,216	$	102.42
$120.91 - 136.42	127,901	3.22 years	133.88		125,459	134.07
$142.67 - 164.35	203,241	5.53 years	154.42		79,119	147.73
	570,622				351,794

Schedule of non-vested stock and restricted stock units

	2017		2016		2015
Shares issued	62,160		58,961		47,038
Weighted‑average per share price on grant date	$	163.18	$	150.48	$	108.97
Recognized compensation expense	$	5,569	$	4,069	$	4,511