Shareholders' Equity Schedule of Other Comprehensive Income (Loss) (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Apr. 01, 2012
Before-tax amount:
Foreign currency translation adjustments	$ 2,280	$ (3,501)
Unrealized gain on investments	38	22
Net pension plan adjustments	(1,894)	(2,119)
Total other comprehensive (loss) income, before tax	(4,136)	1,404
Tax provision:
Foreign currency translation adjustments	0	0
Unrealized gain on investments	(12)	(11)
Net pension plan adjustments	0	0
Total other comprehensive loss, tax provision	(12)	(11)
Net-of-tax amount:
Foreign currency translation adjustments	(2,280)	3,501
Unrealized gain on investments	26	11
Net pension plan adjustments	(1,894)	(2,119)
Total other comprehensive (loss) income	$ (4,148)	$ 1,393