Income Taxes (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Apr. 01, 2018	Dec. 30, 2018
Effective Income Tax Rate	20.00%	(40.50%)
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent	21.00%	21.00%
Employee Service Share-based Compensation, Tax Benefit from Exercise of Stock Options	$ 2,036	$ 6,093
(Provision for) benefit from income taxes	(7,990)	5,806
Decrease in Unrecognized Tax Benefits is Reasonably Possible	7,764
Income Taxes Receivable	9,560		$ 14,475
Income Taxes Receivable, Noncurrent	$ 0		$ 0
Tax Act
(Provision for) benefit from income taxes		3,623
Effective Income Tax Rate Reconciliation, Tax Credit, Foreign, Amount		5,578
Effective Income Tax Rate Reconciliation, Change in Enacted Tax Rate, Amount		$ (1,955)