Components of and Changes in Accumulated Other Comprehensive Income, Net of Related Income Taxes (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 28, 2019	Dec. 29, 2018	Dec. 30, 2017
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance	$ 686,824
Other comprehensive income (loss)	3,663	$ (2,713)	$ (73)
Ending Balance	721,469	686,824
Unrealized Holding (Losses) Gains on Available-for-Sale Securities
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance	(930)	(144)	(71)
Other comprehensive income (loss)	2,050	(786)	(73)
Ending Balance	1,120	(930)	(144)
Foreign Currency Translation
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance	(4,945)	(3,018)	(3,018)
Other comprehensive income (loss)	1,613	(1,927)
Ending Balance	(3,332)	(4,945)	(3,018)
Accumulated Other Comprehensive Income (Loss)
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance	(5,875)	(3,162)	(3,089)
Other comprehensive income (loss)	3,663	(2,713)	(73)
Ending Balance	$ (2,212)	$ (5,875)	$ (3,162)