Revenue Disaggregation of revenues (Details) - USD ($) $ in Thousands	12 Months Ended
	Jan. 01, 2022	Jan. 02, 2021	Dec. 28, 2019
Disaggregation of Revenue [Line Items]
Net sales	$ 4,741,369	$ 3,571,923	$ 3,363,905
North America
Disaggregation of Revenue [Line Items]
Net sales	2,867,934	1,960,503	1,889,573
Europe
Disaggregation of Revenue [Line Items]
Net sales	1,521,031	1,296,668	1,153,787
China
Disaggregation of Revenue [Line Items]
Net sales	253,212	202,093	194,625
South America
Disaggregation of Revenue [Line Items]
Net sales	31,446	38,238	51,168
Other Geographical Areas [Member]
Disaggregation of Revenue [Line Items]
Net sales	67,746	74,421	74,752
Fats [Member]
Disaggregation of Revenue [Line Items]
Net sales	1,380,796	804,737	718,234
Used Cooking Oil [Member]
Disaggregation of Revenue [Line Items]
Net sales	319,145	176,691	185,705
Proteins [Member]
Disaggregation of Revenue [Line Items]
Net sales	1,022,694	830,195	791,284
Bakery [Member]
Disaggregation of Revenue [Line Items]
Net sales	287,424	183,759	191,551
Other Rendering [Member]
Disaggregation of Revenue [Line Items]
Net sales	173,405	178,601	167,870
Food Ingredients, Products and Services [Member]
Disaggregation of Revenue [Line Items]
Net sales	961,617	947,928	894,761
Bioenergy [Member]
Disaggregation of Revenue [Line Items]
Net sales	426,863	293,249	234,691
Biofuels [Member]
Disaggregation of Revenue [Line Items]
Net sales	3,377	20,869	39,568
Other, Products And Services [Member]
Disaggregation of Revenue [Line Items]
Net sales	166,048	135,894	140,241
Food Ingredients [Member]
Disaggregation of Revenue [Line Items]
Net sales	1,271,629	1,185,701	1,119,085
Food Ingredients [Member] | North America
Disaggregation of Revenue [Line Items]
Net sales	286,852	244,929	214,623
Food Ingredients [Member] | Europe
Disaggregation of Revenue [Line Items]
Net sales	663,619	650,671	609,999
Food Ingredients [Member] | China
Disaggregation of Revenue [Line Items]
Net sales	233,766	188,417	178,283
Food Ingredients [Member] | South America
Disaggregation of Revenue [Line Items]
Net sales	31,446	38,238	51,168
Food Ingredients [Member] | Other Geographical Areas [Member]
Disaggregation of Revenue [Line Items]
Net sales	55,946	63,446	65,012
Food Ingredients [Member] | Fats [Member]
Disaggregation of Revenue [Line Items]
Net sales	182,674	142,963	133,898
Food Ingredients [Member] | Used Cooking Oil [Member]
Disaggregation of Revenue [Line Items]
Net sales	0	0	0
Food Ingredients [Member] | Proteins [Member]
Disaggregation of Revenue [Line Items]
Net sales	0	0	0
Food Ingredients [Member] | Bakery [Member]
Disaggregation of Revenue [Line Items]
Net sales	0	0	0
Food Ingredients [Member] | Other Rendering [Member]
Disaggregation of Revenue [Line Items]
Net sales	0	0	0
Food Ingredients [Member] | Food Ingredients, Products and Services [Member]
Disaggregation of Revenue [Line Items]
Net sales	961,617	947,928	894,761
Food Ingredients [Member] | Bioenergy [Member]
Disaggregation of Revenue [Line Items]
Net sales	0	0	0
Food Ingredients [Member] | Biofuels [Member]
Disaggregation of Revenue [Line Items]
Net sales	0	0	0
Food Ingredients [Member] | Other, Products And Services [Member]
Disaggregation of Revenue [Line Items]
Net sales	127,338	94,810	90,426
Fuel Ingredients [Member]
Disaggregation of Revenue [Line Items]
Net sales	430,240	314,118	274,259
Fuel Ingredients [Member] | North America
Disaggregation of Revenue [Line Items]
Net sales	3,377	20,869	39,568
Fuel Ingredients [Member] | Europe
Disaggregation of Revenue [Line Items]
Net sales	426,863	293,249	234,691
Fuel Ingredients [Member] | China
Disaggregation of Revenue [Line Items]
Net sales	0	0	0
Fuel Ingredients [Member] | South America
Disaggregation of Revenue [Line Items]
Net sales	0	0	0
Fuel Ingredients [Member] | Other Geographical Areas [Member]
Disaggregation of Revenue [Line Items]
Net sales	0	0	0
Fuel Ingredients [Member] | Fats [Member]
Disaggregation of Revenue [Line Items]
Net sales	0	0	0
Fuel Ingredients [Member] | Used Cooking Oil [Member]
Disaggregation of Revenue [Line Items]
Net sales	0	0	0
Fuel Ingredients [Member] | Proteins [Member]
Disaggregation of Revenue [Line Items]
Net sales	0	0	0
Fuel Ingredients [Member] | Bakery [Member]
Disaggregation of Revenue [Line Items]
Net sales	0	0	0
Fuel Ingredients [Member] | Other Rendering [Member]
Disaggregation of Revenue [Line Items]
Net sales	0	0	0
Fuel Ingredients [Member] | Food Ingredients, Products and Services [Member]
Disaggregation of Revenue [Line Items]
Net sales	0	0	0
Fuel Ingredients [Member] | Bioenergy [Member]
Disaggregation of Revenue [Line Items]
Net sales	426,863	293,249	234,691
Fuel Ingredients [Member] | Biofuels [Member]
Disaggregation of Revenue [Line Items]
Net sales	3,377	20,869	39,568
Fuel Ingredients [Member] | Other, Products And Services [Member]
Disaggregation of Revenue [Line Items]
Net sales	0	0	0
Feed Ingredients [Member]
Disaggregation of Revenue [Line Items]
Net sales	3,039,500	2,072,104	1,970,561
Feed Ingredients [Member] | North America
Disaggregation of Revenue [Line Items]
Net sales	2,577,705	1,694,705	1,635,382
Feed Ingredients [Member] | Europe
Disaggregation of Revenue [Line Items]
Net sales	430,549	352,748	309,097
Feed Ingredients [Member] | China
Disaggregation of Revenue [Line Items]
Net sales	19,446	13,676	16,342
Feed Ingredients [Member] | South America
Disaggregation of Revenue [Line Items]
Net sales	0	0	0
Feed Ingredients [Member] | Other Geographical Areas [Member]
Disaggregation of Revenue [Line Items]
Net sales	11,800	10,975	9,740
Feed Ingredients [Member] | Fats [Member]
Disaggregation of Revenue [Line Items]
Net sales	1,198,122	661,774	584,336
Feed Ingredients [Member] | Used Cooking Oil [Member]
Disaggregation of Revenue [Line Items]
Net sales	319,145	176,691	185,705
Feed Ingredients [Member] | Proteins [Member]
Disaggregation of Revenue [Line Items]
Net sales	1,022,694	830,195	791,284
Feed Ingredients [Member] | Bakery [Member]
Disaggregation of Revenue [Line Items]
Net sales	287,424	183,759	191,551
Feed Ingredients [Member] | Other Rendering [Member]
Disaggregation of Revenue [Line Items]
Net sales	173,405	178,601	167,870
Feed Ingredients [Member] | Food Ingredients, Products and Services [Member]
Disaggregation of Revenue [Line Items]
Net sales	0	0	0
Feed Ingredients [Member] | Bioenergy [Member]
Disaggregation of Revenue [Line Items]
Net sales	0	0	0
Feed Ingredients [Member] | Biofuels [Member]
Disaggregation of Revenue [Line Items]
Net sales	0	0	0
Feed Ingredients [Member] | Other, Products And Services [Member]
Disaggregation of Revenue [Line Items]
Net sales	$ 38,710	$ 41,084	$ 49,815