Consolidated Statements of Operations - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jul. 03, 2021	Jun. 27, 2020	Jul. 03, 2021	Jun. 27, 2020
Income Statement [Abstract]
Net sales	$ 1,198,669	$ 848,673	$ 2,245,385	$ 1,701,515
Costs and expenses:
Cost of sales and operating expenses	878,073	632,347	1,650,857	1,279,255
Loss (gain) on disposal of property, plant, equipment and other assets	(228)	27	(292)	88
Selling, general and administrative expenses	99,132	90,193	196,530	186,386
Restructuring and asset impairment charges	0	0	778	0
Depreciation and amortization	79,222	83,310	157,756	167,981
Total costs and expenses	1,056,199	805,877	2,005,629	1,633,710
Equity in net income of Diamond Green Diesel	125,788	63,492	228,013	161,312
Operating income	268,258	106,288	467,769	229,117
Other expense:
Interest expense	(15,268)	(17,920)	(31,696)	(37,010)
Foreign currency gain/(loss)	(684)	(1,134)	(1,094)	530
Other expense, net	(1,198)	(1,485)	(2,357)	(3,366)
Total other expense	(17,150)	(20,539)	(35,147)	(39,846)
Equity in net income of other unconsolidated subsidiaries	1,940	692	2,552	1,561
Income before income taxes	253,048	86,441	435,174	190,832
Income tax expense	54,979	19,946	83,687	38,246
Net income	198,069	66,495	351,487	152,586
Net income attributable to noncontrolling interests	(1,487)	(1,056)	(3,139)	(1,637)
Net income attributable to Darling	$ 196,582	$ 65,439	$ 348,348	$ 150,949
Basic income per share (in dollars per share)	$ 1.21	$ 0.40	$ 2.14	$ 0.93
Diluted income per share (in dollars per share)	$ 1.17	$ 0.39	$ 2.08	$ 0.90