Supplemental Disclosure of Cash Flow Information (Detail) - USD ($) $ in Thousands	3 Months Ended
	Apr. 01, 2016	Apr. 03, 2015
Cash paid during period:
Income taxes	$ 1,001	$ 390
Non-cash investing and financing activities:
Unrealized gain (loss) on short-term investments	85	(7)
Vested stock unit awards issued to settle accrued bonuses	6,334	6,169
Accrual for capital expenditures	$ 223	$ 0