Industry Segment, Geographic Information and Significant Customers (Details Textual) $ in Thousands	3 Months Ended								12 Months Ended
	Jan. 02, 2021 USD ($)	Sep. 26, 2020 USD ($)	Jun. 27, 2020 USD ($)	Mar. 28, 2020 USD ($)	Dec. 28, 2019 USD ($)	Sep. 28, 2019 USD ($)	Jun. 29, 2019 USD ($)	Mar. 30, 2019 USD ($)	Jan. 02, 2021 USD ($) segment	Dec. 28, 2019 USD ($)	Dec. 29, 2018 USD ($)
Revenues from External Customers and Long-Lived Assets [Line Items]
Number of operating segments | segment									1
Revenue	$ 544,827	$ 413,145	$ 279,883	$ 192,535	$ 426,778	$ 289,399	$ 260,172	$ 237,661	$ 1,430,390	$ 1,214,010	$ 1,092,584
Customer Concentration Risk | Revenue | Amazon [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Concentration risk percentage									22.70%	21.30%	17.30%
Non-US [Member] | Geographic Concentration Risk | Revenue
Revenues from External Customers and Long-Lived Assets [Line Items]
Concentration risk percentage									47.90%	50.30%	48.70%
Domestic Destination [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue									$ 744,648	$ 603,618	$ 560,995
Geographic Distribution, Foreign [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue									$ 685,742	$ 610,392	$ 531,589