Consolidated Statements of Operations - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Oct. 02, 2021	Sep. 26, 2020	Oct. 02, 2021	Sep. 26, 2020
Income Statement [Abstract]
Net sales	$ 1,185,916	$ 850,569	$ 3,431,301	$ 2,552,084
Costs and expenses:
Cost of sales and operating expenses	859,604	638,368	2,510,461	1,917,623
Loss (gain) on disposal of property, plant, equipment and other assets	(501)	122	(793)	210
Selling, general and administrative expenses	97,275	89,993	293,805	276,379
Restructuring and asset impairment charges	0	0	778	0
Depreciation and amortization	77,826	85,730	235,582	253,711
Total costs and expenses	1,034,204	814,213	3,039,833	2,447,923
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
Other expense:
Interest expense	(15,409)	(18,793)	(47,105)	(55,803)
Foreign currency loss	(205)	(1,239)	(1,299)	(709)
Other expense, net	(853)	(1,912)	(3,210)	(5,278)
Total other expense	(16,467)	(21,944)	(51,614)	(61,790)
Equity in net income of other unconsolidated subsidiaries	1,647	906	4,199	2,467
Income before income taxes	190,843	106,417	626,017	297,249
Income tax expense	42,637	4,812	126,324	43,058
Net income	148,206	101,605	499,693	254,191
Net income attributable to noncontrolling interests	(1,394)	(480)	(4,533)	(2,117)
Net income attributable to Darling	$ 146,812	$ 101,125	$ 495,160	$ 252,074
Basic income per share (in dollars per share)	$ 0.91	$ 0.62	$ 3.04	$ 1.55
Diluted income per share (in dollars per share)	$ 0.88	$ 0.61	$ 2.96	$ 1.51