Changes in Accumulated Other Comprehensive Income (Loss) (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 29, 2019	Sep. 30, 2018	Sep. 29, 2019	Sep. 30, 2018
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance	$ 1,479,412	$ 1,739,940	$ 1,522,354	$ 1,953,646
Other comprehensive (loss) income	(16,630)	7,029	(11,181)	(12,896)
Less: reclassification adjustment for (gains) losses included in net income, net of tax	(345)	(57)	(442)	1,411
Balance	1,482,635	1,667,760	1,482,635	1,667,760
ASU 2016-01
Accumulated Other Comprehensive Income (Loss) [Line Items]
Less: reclassification adjustment for (gains) losses included in net income, net of tax				(3,125)
Foreign Currency Translation Reclassification Adjustments
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance			(12,523)	15,919
Other comprehensive loss before reclassifications, net of tax			(17,019)	(11,568)
Amounts reclassified from accumulated other comprehensive income (loss), net of tax
Other comprehensive (loss) income			(17,019)	(11,568)
Balance	(29,542)	4,351	(29,542)	4,351
Unrealized Gains (Losses) on Marketable Securities
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance			(1,845)	1,362
Other comprehensive loss before reclassifications, net of tax			6,391	(2,555)
Amounts reclassified from accumulated other comprehensive income (loss), net of tax			(442)	1,411
Other comprehensive (loss) income			5,949	(1,144)
Reclassification of tax effects resulting from the Tax Reform Act, net of tax				691
Less: reclassification adjustment for (gains) losses included in net income, net of tax				(3,125)
Balance	4,104	(2,216)	4,104	(2,216)
Amortization of Prior Service Credit
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance			1,328	1,495
Other comprehensive loss before reclassifications, net of tax
Amounts reclassified from accumulated other comprehensive income (loss), net of tax	(37)	(61)	(111)	(184)
Other comprehensive (loss) income			(111)	(184)
Reclassification of tax effects resulting from the Tax Reform Act, net of tax				78
Balance	1,217	1,389	1,217	1,389
Accumulated Other Comprehensive Income (Loss)
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance	(7,591)	(3,504)	(13,040)	18,776
Other comprehensive loss before reclassifications, net of tax			(10,628)	(14,123)
Amounts reclassified from accumulated other comprehensive income (loss), net of tax	(382)	(118)	(553)	(769)
Other comprehensive (loss) income	(16,630)	7,028	(11,181)	(12,896)
Reclassification of tax effects resulting from the Tax Reform Act, net of tax				769
Balance	$ (24,221)	$ 3,524	$ (24,221)	$ 3,524