Schedule of Carrying Amounts and Fair Values of Financial Instruments (Detail) (USD $) In Thousands, unless otherwise specified	Sep. 28, 2014	Dec. 31, 2013		Sep. 29, 2013	Dec. 31, 2012	Mar. 31, 2009
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Cash and cash equivalents, Carrying Value	$ 211,704	$ 341,638		$ 572,868	$ 338,920
Marketable securities, Carrying Value	969,609	857,960
Convertible debt, Carrying Value	0	185,708
Japan loan, Carrying Value						10,000
Carrying Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Cash and cash equivalents, Carrying Value	211,704	341,638
Marketable securities, Carrying Value	969,609	857,960
Convertible debt, Carrying Value		185,708	[1]
Japan loan, Carrying Value		955
Fair Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Cash and cash equivalents, Fair Value	211,704	341,638
Marketable securities, Carrying Value	969,609	857,960
Convertible debt, Fair Value		611,433	[1]
Japan loan, Fair Value		$ 955

[1] The carrying value represents the bifurcated debt component only, while the fair value is based on quoted market prices for the convertible note which includes the equity conversion feature.