Business Segments (Narrative) (Details) $ in Thousands		12 Months Ended
		Dec. 29, 2018 USD ($) segment	Dec. 30, 2017 USD ($)	Dec. 31, 2016 USD ($)
Segment Reporting Information [Line Items]
Number of Business Segments | segment		3
Capital expenditures:	[1]	$ 321,896	$ 274,168	$ 243,523
Fuel Ingredients [Member]
Segment Reporting Information [Line Items]
Capital expenditures:		$ 27,121	$ 24,707	$ 22,323

[1] Excludes capital assets acquired by acquisition in fiscal 2018 of approximately $31.6 million and excludes immaterial capital assets acquired by acquisition in fiscal 2017 and fiscal 2016.