Income Taxes (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 29, 2019	Jun. 30, 2018	Jun. 29, 2019	Jun. 30, 2018
Effective Income Tax Rate Reconciliation, Amount [Abstract]
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent			21.00%
Provision (benefit) at statutory tax rate	$ (126,025)	$ 46,771	$ (84,798)	$ 85,928
State taxes, net of federal benefit	(11,533)	3,732	(7,504)	7,984
International effective tax rate differential	3,238	(758)	8,217	2,798
U.S. Tax on foreign earnings	4,953	2,592	9,880	8,213
Changes in tax accruals	902	306	920	1,293
Tax credits	(1,971)	(1,868)	(4,001)	(3,737)
Impairment of goodwill	76,153	0	76,153	0
Tax Act's impact on deferred taxes	0	0	0	(4,340)
Other	1,914	906	2,671	132
Provision (benefit) for income taxes	$ (52,369)	$ 51,681	$ 1,538	$ 98,271