Guarantor Financial Information (Condensed Consolidated Statements of Comprehensive Income) (Loss) (Details) - USD ($) $ in Thousands	3 Months Ended				6 Months Ended
	Jun. 29, 2019	Mar. 30, 2019	Jun. 30, 2018	Mar. 31, 2018	Jun. 29, 2019	Jun. 30, 2018
Net income/(loss)	$ 31,044	$ 19,640	$ (29,138)	$ 98,075	$ 50,684	$ 68,937
Other comprehensive income, net of tax:
Foreign currency translation	16,326	(4,886)	(76,837)	17,295	11,440	(59,542)
Pension adjustments	859		666		1,717	1,333
Total other comprehensive income/(loss), net of tax	20,791		(75,724)		14,826	(59,345)
Total comprehensive income/(loss)	51,835		(104,862)		65,510	9,592
Comprehensive income attributable to noncontrolling interests	3,315		1,232		6,702	2,519
Comprehensive income/(loss) attributable to Darling	48,520		(106,094)		58,808	7,073
Parent [Member]
Net income/(loss)	31,044		(29,138)		50,684	68,937
Other comprehensive income, net of tax:
Foreign currency translation	(326)		1,116		181	1,116
Pension adjustments	766		565		1,533	1,131
Total other comprehensive income/(loss), net of tax	462		2,128		1,736	1,111
Total comprehensive income/(loss)	31,506		(27,010)		52,420	70,048
Comprehensive income attributable to noncontrolling interests	0		0		0	0
Comprehensive income/(loss) attributable to Darling	31,506		(27,010)		52,420	70,048
Guarantors [Member]
Net income/(loss)	16,819		35,348		35,340	70,625
Other comprehensive income, net of tax:
Foreign currency translation	0		(53,387)		0	(53,387)
Pension adjustments	0		0		0	0
Total other comprehensive income/(loss), net of tax	0		(53,387)		0	(53,387)
Total comprehensive income/(loss)	16,819		(18,039)		35,340	17,238
Comprehensive income attributable to noncontrolling interests	0		0		0	0
Comprehensive income/(loss) attributable to Darling	16,819		(18,039)		35,340	17,238
Non-guarantors [Member]
Net income/(loss)	51,861		(1,189)		87,967	108,414
Other comprehensive income, net of tax:
Foreign currency translation	16,652		(24,566)		11,259	(7,271)
Pension adjustments	93		101		184	202
Total other comprehensive income/(loss), net of tax	20,329		(24,465)		13,090	(7,069)
Total comprehensive income/(loss)	72,190		(25,654)		101,057	101,345
Comprehensive income attributable to noncontrolling interests	3,315		1,232		6,702	2,519
Comprehensive income/(loss) attributable to Darling	68,875		(26,886)		94,355	98,826
Natural Gas Swap [Member]
Other comprehensive income, net of tax:
Derivative adjustments	0		0	22	0	22
Natural Gas Swap [Member] | Parent [Member]
Other comprehensive income, net of tax:
Derivative adjustments						22
Natural Gas Swap [Member] | Guarantors [Member]
Other comprehensive income, net of tax:
Derivative adjustments						0
Natural Gas Swap [Member] | Non-guarantors [Member]
Other comprehensive income, net of tax:
Derivative adjustments						0
Corn Option [Member]
Other comprehensive income, net of tax:
Derivative adjustments	22		447	$ (1,605)	22	(1,158)
Corn Option [Member] | Parent [Member]
Other comprehensive income, net of tax:
Derivative adjustments	22		447		22	(1,158)
Corn Option [Member] | Guarantors [Member]
Other comprehensive income, net of tax:
Derivative adjustments	0		0		0	0
Corn Option [Member] | Non-guarantors [Member]
Other comprehensive income, net of tax:
Derivative adjustments	0		0		0	0
Heating Oil Swaps And Options [Member]
Other comprehensive income, net of tax:
Derivative adjustments	2,133		0		2,133	0
Heating Oil Swaps And Options [Member] | Parent [Member]
Other comprehensive income, net of tax:
Derivative adjustments	0				0
Heating Oil Swaps And Options [Member] | Guarantors [Member]
Other comprehensive income, net of tax:
Derivative adjustments	0				0
Heating Oil Swaps And Options [Member] | Non-guarantors [Member]
Other comprehensive income, net of tax:
Derivative adjustments	2,133				2,133
Foreign Exchange Contract [Member]
Other comprehensive income, net of tax:
Derivative adjustments	1,451	$ (1,937)	0		(486)	0
Foreign Exchange Contract [Member] | Parent [Member]
Other comprehensive income, net of tax:
Derivative adjustments	0				0
Foreign Exchange Contract [Member] | Guarantors [Member]
Other comprehensive income, net of tax:
Derivative adjustments	0				0
Foreign Exchange Contract [Member] | Non-guarantors [Member]
Other comprehensive income, net of tax:
Derivative adjustments	1,451				(486)
Eliminations [Member]
Net income/(loss)	(68,680)		(34,159)		(123,307)	(179,039)
Other comprehensive income, net of tax:
Foreign currency translation	0		0		0	0
Pension adjustments	0		0		0	0
Derivative adjustments	0		0		0	0
Total other comprehensive income/(loss), net of tax	0		0		0	0
Total comprehensive income/(loss)	(68,680)		(34,159)		(123,307)	(179,039)
Comprehensive income attributable to noncontrolling interests	0		0		0	0
Comprehensive income/(loss) attributable to Darling	$ (68,680)		$ (34,159)		$ (123,307)	(179,039)
Eliminations [Member] | Natural Gas Swap [Member]
Other comprehensive income, net of tax:
Derivative adjustments						$ 0