CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 29, 2019	Sep. 30, 2018	Sep. 29, 2019	Sep. 30, 2018
Net income	$ 135,860	$ 119,981	$ 342,395	$ 307,991
Other comprehensive income, net of tax:
Foreign currency translation adjustment, net of tax of $0	(18,002)	7,213	(17,019)	(11,568)
Available-for-sale marketable securities:
Unrealized gains (losses) on marketable securities arising during period, net of tax of $507, $(62), $1,762, $(806), respectively	1,754	(66)	6,391	(2,555)
Less: Reclassification adjustment for (gains) losses included in net income, net of tax of $(99), $(17), $(125), $(6), respectively	(345)	(57)	(442)	1,411
Other Comprehensive Income (Loss), Available-for-sale Securities Adjustment, Net of Tax, Total	1,409	(123)	5,949	(1,144)
Defined benefit pension and post-retirement plans:
Amortization of prior service benefit included in net periodic pension and post-retirement benefit, net of tax of $(11), $(18), $(32), $(53), respectively	(37)	(61)	(111)	(184)
Other comprehensive (loss) income	(16,630)	7,029	(11,181)	(12,896)
Comprehensive income	$ 119,230	$ 127,010	$ 331,214	$ 295,095