Guarantor Financial Information (Condensed Consolidated Statements of Comprehensive Income) (Loss) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 28, 2020	Mar. 30, 2019
Net income	$ 86,091	$ 19,640
Other comprehensive income, net of tax:
Foreign currency translation	(65,236)	(4,886)
Pension adjustments	648	858
Total other comprehensive income/(loss), net of tax	(62,733)	(5,965)
Total comprehensive income/(loss)	23,358	13,675
Comprehensive income attributable to noncontrolling interests	492	3,387
Comprehensive income attributable to Darling	22,866	10,288
Parent [Member]
Net income	86,091	19,640
Other comprehensive income, net of tax:
Foreign currency translation	651	507
Pension adjustments	518	767
Total other comprehensive income/(loss), net of tax	1,305	1,274
Total comprehensive income/(loss)	87,396	20,914
Comprehensive income attributable to noncontrolling interests	0	0
Comprehensive income attributable to Darling	87,396	20,914
Guarantors [Member]
Net income	20,112	18,521
Other comprehensive income, net of tax:
Foreign currency translation	(128,994)	0
Pension adjustments	0	0
Total other comprehensive income/(loss), net of tax	(128,994)	0
Total comprehensive income/(loss)	(108,882)	18,521
Comprehensive income attributable to noncontrolling interests	0	0
Comprehensive income attributable to Darling	(108,882)	18,521
Non-guarantors [Member]
Net income	101,827	36,106
Other comprehensive income, net of tax:
Foreign currency translation	63,107	(5,393)
Pension adjustments	130	91
Total other comprehensive income/(loss), net of tax	64,956	(7,239)
Total comprehensive income/(loss)	166,783	28,867
Comprehensive income attributable to noncontrolling interests	492	3,387
Comprehensive income attributable to Darling	166,291	25,480
Eliminations [Member]
Other comprehensive income, net of tax:
Derivative adjustments		0
Corn Option [Member]
Other comprehensive income, net of tax:
Derivative adjustments	136	0
Corn Option [Member] | Parent [Member]
Other comprehensive income, net of tax:
Derivative adjustments	136
Corn Option [Member] | Guarantors [Member]
Other comprehensive income, net of tax:
Derivative adjustments	0
Corn Option [Member] | Non-guarantors [Member]
Other comprehensive income, net of tax:
Derivative adjustments	0
Heating Oil Swaps And Options [Member]
Other comprehensive income, net of tax:
Derivative adjustments	10,870	0
Heating Oil Swaps And Options [Member] | Parent [Member]
Other comprehensive income, net of tax:
Derivative adjustments	0
Heating Oil Swaps And Options [Member] | Guarantors [Member]
Other comprehensive income, net of tax:
Derivative adjustments	0
Heating Oil Swaps And Options [Member] | Non-guarantors [Member]
Other comprehensive income, net of tax:
Derivative adjustments	10,870
Foreign Exchange Contract [Member]
Other comprehensive income, net of tax:
Derivative adjustments	(9,151)	(1,937)
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	(9,151)	(1,937)
Eliminations [Member]
Net income	(121,939)	(54,627)
Other comprehensive income, net of tax:
Foreign currency translation	0	0
Pension adjustments	0	0
Derivative adjustments	0
Total other comprehensive income/(loss), net of tax	0	0
Total comprehensive income/(loss)	(121,939)	(54,627)
Comprehensive income attributable to noncontrolling interests	0	0
Comprehensive income attributable to Darling	$ (121,939)	$ (54,627)