Quarterly Financial Data (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 30, 2017	Sep. 30, 2017	Jul. 01, 2017	Apr. 01, 2017	Dec. 31, 2016	Oct. 01, 2016	Jul. 02, 2016	Apr. 02, 2016	Dec. 30, 2017	Dec. 31, 2016	Jan. 02, 2016
Quarterly Financial Information Disclosure [Abstract]
Net Sales	$ 952,549	$ 936,262	$ 894,930	$ 878,510	$ 885,758	$ 852,018	$ 875,777	$ 778,375	$ 3,662,251	$ 3,391,928	$ 3,391,255
Segment operating income/(loss)	35,026	33,310	37,063	31,414	35,380	35,528	54,467	26,692	136,813	152,067	142,644
Income from operations before income taxes	21,934	14,980	18,070	9,216	47,893	28,146	41,974	4,526	64,200	122,539	98,780
Net income	106,944	8,684	10,328	7,398	41,680	28,890	33,991	2,663	133,354	107,224	85,279
Net income attributable to noncontrolling interests	(1,215)	(923)	(1,179)	(1,569)	(1,139)	(196)	(1,992)	(1,584)	(4,886)	(4,911)	(6,748)
Net income attributable to Darling	$ 105,729	$ 7,761	$ 9,149	$ 5,829	$ 40,541	$ 28,694	$ 31,999	$ 1,079	$ 128,468	$ 102,313	$ 78,531
Basic (in dollars per share)	$ 0.64	$ 0.05	$ 0.06	$ 0.04	$ 0.25	$ 0.17	$ 0.19	$ 0.01	$ 0.78	$ 0.62	$ 0.48
Diluted (in dollars per share)	$ 0.63	$ 0.05	$ 0.05	$ 0.04	$ 0.25	$ 0.17	$ 0.19	$ 0.01	$ 0.77	$ 0.62	$ 0.48
Sales Deductions		$ 1,400	$ 1,400	$ 1,600	$ 1,500	$ 1,800	$ 1,600	$ 1,300
Provisional income tax Benefit									$ 75,000
Insured Event, Gain (Loss)										$ 5,600