Business Segments (Narrative) (Details) $ in Thousands		12 Months Ended
		Jan. 02, 2021 USD ($) segment	Dec. 28, 2019 USD ($)	Dec. 29, 2018 USD ($)
Segment Reporting Information [Line Items]
Number of Business Segments | segment		3
Capital expenditures:	[1]	$ 280,115	$ 359,498	$ 321,896
Fuel Ingredients [Member]
Segment Reporting Information [Line Items]
Capital expenditures:		$ 30,638	$ 23,964	$ 27,121

[1] Excludes capital assets acquired by acquisition in fiscal 2020 and fiscal 2018 of approximately $18.4 million and $31.6 million, respectively.