Guarantor Financial Information (Condensed Consolidated Statements of Operations) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 29, 2019	Jun. 30, 2018	Jun. 29, 2019	Jun. 30, 2018
Net sales	$ 827,324	$ 846,646	$ 1,662,428	$ 1,722,020
Costs and expenses:
Cost of sales and operating expenses	644,716	652,239	1,295,629	1,330,800
Loss (gain) on disposal of property, plant, equipment and other assets	(13,926)	762	(18,176)	300
Selling, general and administrative expenses	81,017	78,558	166,020	165,460
Restructuring and impairment charges	0	14,965	0	14,965
Depreciation and amortization	79,486	78,454	158,650	157,073
Total costs and expenses	791,293	824,978	1,602,123	1,668,598
Operating income	36,031	21,668	60,305	53,422
Interest expense	(20,853)	(23,016)	(40,729)	(46,140)
Debt extinguishment costs	(12,126)	(23,509)	(12,126)	(23,509)
Foreign currency loss	(388)	(3,495)	(1,120)	(4,976)
Loss on disposal of subsidiaries	0	(15,538)	0	(15,538)
Other expense, net	(2,019)	1,199	(4,544)	(1,317)
Equity in net income of unconsolidated subsidiaries	38,175	15,236	61,948	112,390
Earnings in investments in subsidiaries	0	0	0	0
Income/(loss) before taxes	38,820	(27,455)	63,734	74,332
Income tax expense	7,776	1,683	13,050	5,395
Net income attributable to noncontrolling interests	(4,786)	(1,282)	(6,414)	(2,052)
Net income/(loss) attributable to Darling	26,258	(30,420)	44,270	66,885
Parent [Member]
Net sales	156,927	135,196	317,157	254,821
Costs and expenses:
Cost of sales and operating expenses	125,586	102,171	253,910	198,290
Loss (gain) on disposal of property, plant, equipment and other assets	(26)	50	42	(201)
Selling, general and administrative expenses	40,570	36,393	87,993	80,171
Restructuring and impairment charges		0		0
Depreciation and amortization	14,224	11,577	28,597	22,636
Total costs and expenses	180,354	150,191	370,542	300,896
Operating income	(23,427)	(14,995)	(53,385)	(46,075)
Interest expense	(15,078)	(14,193)	(29,105)	(28,557)
Debt extinguishment costs	(12,126)	(15,635)	(12,126)	(15,635)
Foreign currency loss	3	(414)	(1)	(437)
Loss on disposal of subsidiaries		(15,538)		(15,538)
Other expense, net	(1,285)	(10,204)	(2,852)	(13,614)
Equity in net income of unconsolidated subsidiaries	(1,027)	(577)	(1,918)	(1,075)
Earnings in investments in subsidiaries	68,680	34,159	123,307	179,039
Income/(loss) before taxes	15,740	(37,397)	23,920	58,108
Income tax expense	(10,518)	(6,977)	(20,350)	(8,777)
Net income attributable to noncontrolling interests	0	0	0	0
Net income/(loss) attributable to Darling	26,258	(30,420)	44,270	66,885
Guarantors [Member]
Net sales	325,744	348,497	655,735	693,100
Costs and expenses:
Cost of sales and operating expenses	268,582	275,696	540,253	547,061
Loss (gain) on disposal of property, plant, equipment and other assets	(511)	(87)	(4,988)	(215)
Selling, general and administrative expenses	10,776	12,425	22,723	25,262
Restructuring and impairment charges		0		0
Depreciation and amortization	25,165	25,942	51,277	52,233
Total costs and expenses	304,012	313,976	609,265	624,341
Operating income	21,732	34,521	46,470	68,759
Interest expense	(24)	3,240	(56)	7,003
Debt extinguishment costs	0	0	0	0
Foreign currency loss	1	(31)	1	(94)
Loss on disposal of subsidiaries		0		0
Other expense, net	(764)	1,810	(1,976)	484
Equity in net income of unconsolidated subsidiaries	0	0	0	0
Earnings in investments in subsidiaries	0	0	0	0
Income/(loss) before taxes	20,945	39,540	44,439	76,152
Income tax expense	4,126	4,192	9,099	5,527
Net income attributable to noncontrolling interests	0	0	0	0
Net income/(loss) attributable to Darling	16,819	35,348	35,340	70,625
Non-guarantors [Member]
Net sales	399,339	423,466	803,250	891,274
Costs and expenses:
Cost of sales and operating expenses	305,234	334,885	615,180	702,624
Loss (gain) on disposal of property, plant, equipment and other assets	(13,389)	799	(13,230)	716
Selling, general and administrative expenses	29,671	29,740	55,304	60,027
Restructuring and impairment charges		14,965		14,965
Depreciation and amortization	40,097	40,935	78,776	82,204
Total costs and expenses	361,613	421,324	736,030	860,536
Operating income	37,726	2,142	67,220	30,738
Interest expense	(5,751)	(12,063)	(11,568)	(24,586)
Debt extinguishment costs	0	(7,874)	0	(7,874)
Foreign currency loss	(392)	(3,050)	(1,120)	(4,445)
Loss on disposal of subsidiaries		0		0
Other expense, net	30	9,593	284	11,813
Equity in net income of unconsolidated subsidiaries	39,202	15,813	63,866	113,465
Earnings in investments in subsidiaries	0	0	0	0
Income/(loss) before taxes	70,815	4,561	118,682	119,111
Income tax expense	14,168	4,468	24,301	8,645
Net income attributable to noncontrolling interests	(4,786)	(1,282)	(6,414)	(2,052)
Net income/(loss) attributable to Darling	51,861	(1,189)	87,967	108,414
Eliminations [Member]
Costs and expenses:
Debt extinguishment costs	0	0	0	0
Eliminations [Member]
Net sales	(54,686)	(60,513)	(113,714)	(117,175)
Costs and expenses:
Cost of sales and operating expenses	(54,686)	(60,513)	(113,714)	(117,175)
Loss (gain) on disposal of property, plant, equipment and other assets	0	0	0	0
Selling, general and administrative expenses	0	0	0	0
Restructuring and impairment charges		0		0
Depreciation and amortization	0	0	0	0
Total costs and expenses	(54,686)	(60,513)	(113,714)	(117,175)
Operating income	0	0	0	0
Interest expense	0	0	0	0
Foreign currency loss	0	0	0	0
Loss on disposal of subsidiaries		0		0
Other expense, net	0	0	0	0
Equity in net income of unconsolidated subsidiaries	0	0	0	0
Earnings in investments in subsidiaries	(68,680)	(34,159)	(123,307)	(179,039)
Income/(loss) before taxes	(68,680)	(34,159)	(123,307)	(179,039)
Income tax expense	0	0	0	0
Net income attributable to noncontrolling interests	0	0	0	0
Net income/(loss) attributable to Darling	$ (68,680)	$ (34,159)	$ (123,307)	$ (179,039)