Summary of Stock Options under Employee Equity Incentive Plan and Stock Option Plan for Non-Employee Directors (Detail) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 30, 2017 USD ($) $ / shares shares
Shares
Outstanding at beginning of period | shares	1,348,233
Granted | shares	15,373
Forfeited | shares	(12,208)
Expired | shares	0
Exercised | shares	(194,401)
Outstanding at end of period | shares	1,156,997
Exercisable at end of period | shares	182,242
Vested and expected to vest at end of period | shares	562,478
Weighted-Average Exercise Price
Outstanding at beginning of period | $ / shares	$ 141.98
Granted | $ / shares	150.10
Forfeited | $ / shares	160.47
Expired | $ / shares	0
Exercised | $ / shares	79.78
Outstanding at end of period | $ / shares	158.53
Exercisable at end of period | $ / shares	98.78
Vested and expected to vest at end of period | $ / shares	$ 115.47
Weighted-Average Remaining Contractual Term
Outstanding at end of period	6 years 3 months 11 days
Exercisable at end of period	3 years 6 months 29 days
Vested and expected to vest at end of period	4 years 5 months 27 days
Aggregate Intrinsic Value
Outstanding at end of period | $	$ 45,877
Exercisable at end of period | $	17,554
Vested and expected to vest at end of period | $	$ 44,461