Business Segments (Details) - USD ($) $ in Thousands	3 Months Ended			9 Months Ended
	Oct. 02, 2021	Apr. 03, 2021	Sep. 26, 2020	Oct. 02, 2021	Sep. 26, 2020	Jan. 02, 2021
Segment Reporting, Revenue Reconciling Item [Line Items]
Net sales	$ 1,185,916		$ 850,569	$ 3,431,301	$ 2,552,084
Cost of sales and operating expenses	859,604		638,368	2,510,461	1,917,623
Gain on sale of assets	501		(122)	793	(210)
Selling, general and administrative expenses	97,275		89,993	293,805	276,379
Restructuring and asset impairment charges	0	$ 800	0	778	0
Depreciation and amortization	77,826		85,730	235,582	253,711
Equity in net income of Diamond Green Diesel	53,951		91,099	281,964	252,411
Operating income	205,663		127,455	673,432	356,572
Equity in net income of other unconsolidated subsidiaries	1,647		906	4,199	2,467
Total other expense	(16,467)		(21,944)	(51,614)	(61,790)
Income before income taxes	190,843		106,417	626,017	297,249
Segment Assets	5,925,720			5,925,720		$ 5,613,331
Feed Ingredients
Segment Reporting, Revenue Reconciling Item [Line Items]
Net sales	769,626		483,025	2,193,002	1,499,340
Cost of sales and operating expenses	553,662		361,576	1,584,667	1,117,931
Gross Margin	215,964		121,449	608,335	381,409
Gain on sale of assets	(229)		167	(490)	293
Selling, general and administrative expenses	54,997		49,028	162,594	153,459
Restructuring and asset impairment charges				0
Depreciation and amortization	53,824		53,764	162,404	159,968
Equity in net income of Diamond Green Diesel	0		0	0	0
Operating income	107,372		18,490	283,827	67,689
Equity in net income of other unconsolidated subsidiaries	1,647		906	4,199	2,467
Segment income/(loss)	109,019		19,396	288,026	70,156
Segment Assets	2,787,376			2,787,376		2,708,922
Food Ingredients
Segment Reporting, Revenue Reconciling Item [Line Items]
Net sales	311,856		291,842	926,952	841,070
Cost of sales and operating expenses	241,308		226,745	706,260	652,334
Gross Margin	70,548		65,097	220,692	188,736
Gain on sale of assets	(8)		16	(1)	(30)
Selling, general and administrative expenses	24,417		23,366	75,150	71,406
Restructuring and asset impairment charges				0
Depreciation and amortization	14,933		20,648	45,666	60,925
Equity in net income of Diamond Green Diesel	0		0	0	0
Operating income	31,206		21,067	99,877	56,435
Equity in net income of other unconsolidated subsidiaries	0		0	0	0
Segment income/(loss)	31,206		21,067	99,877	56,435
Segment Assets	1,213,831			1,213,831		1,335,769
Fuel Ingredients
Segment Reporting, Revenue Reconciling Item [Line Items]
Net sales	104,434		75,702	311,347	211,674
Cost of sales and operating expenses	64,634		50,047	219,534	147,358
Gross Margin	39,800		25,655	91,813	64,316
Gain on sale of assets	(264)		(61)	(302)	(53)
Selling, general and administrative expenses	4,481		5,038	13,822	10,645
Restructuring and asset impairment charges				778
Depreciation and amortization	6,361		8,633	19,214	24,705
Equity in net income of Diamond Green Diesel	53,951		91,099	281,964	252,411
Operating income	83,173		103,144	340,265	281,430
Equity in net income of other unconsolidated subsidiaries	0		0	0	0
Segment income/(loss)	83,173		103,144	340,265	281,430
Segment Assets	1,413,049			1,413,049		1,160,132
Corporate
Segment Reporting, Revenue Reconciling Item [Line Items]
Net sales	0		0	0	0
Cost of sales and operating expenses	0		0	0	0
Gross Margin	0		0	0	0
Gain on sale of assets	0		0	0	0
Selling, general and administrative expenses	13,380		12,561	42,239	40,869
Restructuring and asset impairment charges				0
Depreciation and amortization	2,708		2,685	8,298	8,113
Equity in net income of Diamond Green Diesel	0		0	0	0
Operating income	(16,088)		(15,246)	(50,537)	(48,982)
Equity in net income of other unconsolidated subsidiaries	0		0	0	0
Segment income/(loss)	(16,088)		(15,246)	(50,537)	(48,982)
Segment Assets	511,464			511,464		408,508
Total
Segment Reporting, Revenue Reconciling Item [Line Items]
Net sales	1,185,916		850,569	3,431,301	2,552,084
Cost of sales and operating expenses	859,604		638,368	2,510,461	1,917,623
Gross Margin	326,312		212,201	920,840	634,461
Gain on sale of assets	(501)		122	(793)	210
Selling, general and administrative expenses	97,275		89,993	293,805	276,379
Restructuring and asset impairment charges				778
Depreciation and amortization	77,826		85,730	235,582	253,711
Equity in net income of Diamond Green Diesel	53,951		91,099	281,964	252,411
Operating income	205,663		127,455	673,432	356,572
Equity in net income of other unconsolidated subsidiaries	1,647		906	4,199	2,467
Segment income/(loss)	207,310		$ 128,361	677,631	$ 359,039
Segment Assets	$ 5,925,720			$ 5,925,720		$ 5,613,331