Supplemental Disclosure of Cash Flow Information (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 28, 2013	Jun. 29, 2012	Jun. 28, 2013	Jun. 29, 2012
Cash paid during period:
Income taxes			$ 7,902	$ 7,307
Non-cash investing and financing activities:
Unrealized (loss) gain on short-term investments	(10)	(14)	(22)	12
Vested stock unit awards issued to settle accrued bonuses			$ 5,807	$ 5,343