Business Segments (Details) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Apr. 03, 2021	Mar. 28, 2020	Jan. 02, 2021
Segment Reporting, Revenue Reconciling Item [Line Items]
Net sales	$ 1,046,716	$ 852,842
Cost of sales and operating expenses	772,784	646,908
Loss/(gain) on sale of assets	64	(61)
Selling, general and administrative expenses	97,398	96,193
Restructuring and asset impairment charges	778	0	$ 800
Depreciation and amortization	78,534	84,671
Equity in net income of Diamond Green Diesel	102,225	97,820
Operating income	199,511	122,829
Equity in net income of other unconsolidated subsidiaries	612	869
Total other expense	(17,997)	(19,307)
Income before income taxes	182,126	104,391
Segment Assets	5,591,447		5,613,331
Feed Ingredients
Segment Reporting, Revenue Reconciling Item [Line Items]
Net sales	651,444	512,625
Cost of sales and operating expenses	474,581	388,453
Gross Margin	176,863	124,172
Loss/(gain) on sale of assets	(139)	50
Selling, general and administrative expenses	52,620	53,947
Restructuring and asset impairment charges	0
Depreciation and amortization	54,609	53,521
Equity in net income of Diamond Green Diesel	0	0
Operating income	69,773	16,654
Equity in net income of other unconsolidated subsidiaries	612	869
Segment income/(loss)	70,385	17,523
Segment Assets	2,708,035		2,708,922
Food Ingredients
Segment Reporting, Revenue Reconciling Item [Line Items]
Net sales	298,065	270,294
Cost of sales and operating expenses	226,413	205,430
Gross Margin	71,652	64,864
Loss/(gain) on sale of assets	55	2
Selling, general and administrative expenses	25,191	25,476
Restructuring and asset impairment charges	0
Depreciation and amortization	14,883	20,305
Equity in net income of Diamond Green Diesel	0	0
Operating income	31,523	19,081
Equity in net income of other unconsolidated subsidiaries	0	0
Segment income/(loss)	31,523	19,081
Segment Assets	1,235,547		1,335,769
Fuel Ingredients
Segment Reporting, Revenue Reconciling Item [Line Items]
Net sales	97,207	69,923
Cost of sales and operating expenses	71,790	53,025
Gross Margin	25,417	16,898
Loss/(gain) on sale of assets	20	9
Selling, general and administrative expenses	4,867	1,654
Restructuring and asset impairment charges	778
Depreciation and amortization	6,155	8,092
Equity in net income of Diamond Green Diesel	102,225	97,820
Operating income	115,822	104,963
Equity in net income of other unconsolidated subsidiaries	0	0
Segment income/(loss)	115,822	104,963
Segment Assets	1,229,461		1,160,132
Corporate
Segment Reporting, Revenue Reconciling Item [Line Items]
Net sales	0	0
Cost of sales and operating expenses	0	0
Gross Margin	0	0
Loss/(gain) on sale of assets	0	0
Selling, general and administrative expenses	14,720	15,116
Restructuring and asset impairment charges	0
Depreciation and amortization	2,887	2,753
Equity in net income of Diamond Green Diesel	0	0
Operating income	(17,607)	(17,869)
Equity in net income of other unconsolidated subsidiaries	0	0
Segment income/(loss)	(17,607)	(17,869)
Segment Assets	418,404		408,508
Total
Segment Reporting, Revenue Reconciling Item [Line Items]
Net sales	1,046,716	852,842
Cost of sales and operating expenses	772,784	646,908
Gross Margin	273,932	205,934
Loss/(gain) on sale of assets	(64)	61
Selling, general and administrative expenses	97,398	96,193
Restructuring and asset impairment charges	778
Depreciation and amortization	78,534	84,671
Equity in net income of Diamond Green Diesel	102,225	97,820
Operating income	199,511	122,829
Equity in net income of other unconsolidated subsidiaries	612	869
Segment income/(loss)	200,123	$ 123,698
Segment Assets	$ 5,591,447		$ 5,613,331