Changes in Accumulated Other Comprehensive Income (Loss) (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jul. 01, 2018	Jul. 02, 2017	Jul. 01, 2018	Jul. 02, 2017
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other comprehensive income (loss) before reclassifications, net of tax			$ (21,270)	$ 26,442
Amounts reclassified from accumulated other comprehensive income (loss), net of tax			1,346	(313)
Other comprehensive (loss) income	$ (29,384)	$ 16,815	(19,924)	26,129
Reclassification of income tax effects from the Tax Reform Act, net of tax			769
Reclassification of unrealized gains on equity securities, net of tax	(199)	(83)	1,469	(177)
Balance	1,739,940		1,739,940
ASU 2016-01
Accumulated Other Comprehensive Income (Loss) [Line Items]
Reclassification of unrealized gains on equity securities, net of tax			(3,125)
Foreign Currency Translation Reclassification Adjustments
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance			15,919	(21,921)
Other comprehensive income (loss) before reclassifications, net of tax			(18,781)	24,944
Other comprehensive (loss) income			(18,781)	24,944
Balance	(2,862)	3,023	(2,862)	3,023
Unrealized Gains (Losses) on Marketable Securities
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance			1,362	(60)
Other comprehensive income (loss) before reclassifications, net of tax			(2,489)	1,498
Amounts reclassified from accumulated other comprehensive income (loss), net of tax			1,469	(177)
Other comprehensive (loss) income			(1,020)	1,321
Reclassification of income tax effects from the Tax Reform Act, net of tax			691
Balance	(2,092)	1,261	(2,092)	1,261
Unrealized Gains (Losses) on Marketable Securities | ASU 2016-01
Accumulated Other Comprehensive Income (Loss) [Line Items]
Reclassification of unrealized gains on equity securities, net of tax			(3,125)
Amortization of Prior Service Credit
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance			1,495	1,767
Amounts reclassified from accumulated other comprehensive income (loss), net of tax	(61)	(68)	(123)	(136)
Other comprehensive (loss) income			(123)	(136)
Reclassification of income tax effects from the Tax Reform Act, net of tax			78
Balance	1,450	1,631	1,450	1,631
Accumulated Other Comprehensive Income (Loss)
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance			18,776	(20,214)
Amounts reclassified from accumulated other comprehensive income (loss), net of tax	(260)	(151)	1,346	(313)
Balance	$ (3,504)	$ 5,915	$ (3,504)	$ 5,915