Guarantor Financial Information Condensed Consolidated Statements of Operations (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended								12 Months Ended
	Jan. 03, 2015	Sep. 27, 2014	Jun. 28, 2014	Mar. 29, 2014	Dec. 28, 2013	Sep. 28, 2013	Jun. 29, 2013	Mar. 30, 2013	Jan. 03, 2015	Dec. 28, 2013	Dec. 29, 2012
Net Sales	$ 1,000,203	$ 978,665	$ 1,031,283	$ 946,292	$ 447,939	$ 445,130	$ 443,542	$ 465,657	$ 3,956,443	$ 1,802,268	$ 1,772,552
Costs and expenses:
Cost of sales and operating expenses		22,900	24,300	14,900	19,200	19,300	19,900	20,200	3,123,171	1,339,819	1,303,727
Selling, general and administrative expense									374,580	170,825	151,713
Depreciation and amortization									269,517	98,787	85,371
Business Combination, Acquisition and Integration Related Costs	2,400	2,200	4,200	15,900					24,667	23,271	0
Total costs and expenses									3,791,935	1,632,702	1,540,811
Operating income	39,662	49,925	75,485	(564)	18,536	41,652	50,802	58,576	164,508	169,566	231,741
Interest expense									(135,416)	(38,108)	(24,054)
Foreign currency gains (losses)				12,600					(13,548)	28,107	0
Other income/(expense), net									299	(3,547)	1,760
Equity in net income of unconsolidated subsidiaries									65,609	7,660	(2,662)
Earnings in investments in subsidiaries									0	0	0
Income from operations before income taxes	73,580	27,090	50,078	(69,296)	23,078	45,024	42,753	52,823	81,452	163,678	206,785
Income taxes (benefit)									13,141	54,711	76,015
Net Income (Loss) Attributable to Noncontrolling Interest	1,155	(1,636)	(1,818)	(1,797)					(4,096)	0	0
Net income attributable to Darling	69,943	14,318	32,757	(52,803)	22,493	27,651	26,418	32,405	64,215	108,967	130,770
Issuer [Member]
Net Sales									557,316	708,166	679,432
Costs and expenses:
Cost of sales and operating expenses									421,883	559,117	532,734
Selling, general and administrative expense									145,258	91,723	80,432
Depreciation and amortization									31,183	24,794	23,542
Business Combination, Acquisition and Integration Related Costs									20,410	14,074
Total costs and expenses									618,734	689,708	636,708
Operating income									(61,418)	18,458	42,724
Interest expense									(97,912)	(36,964)	(24,047)
Foreign currency gains (losses)									(12,244)	27,516
Other income/(expense), net									(3,717)	(3,373)	(1,572)
Equity in net income of unconsolidated subsidiaries									0	0	0
Earnings in investments in subsidiaries									223,790	105,178	119,953
Income from operations before income taxes									48,499	110,815	137,058
Income taxes (benefit)									(15,716)	1,848	6,288
Net Income (Loss) Attributable to Noncontrolling Interest									0
Net income attributable to Darling									64,215	108,967	130,770
Guarantors [Member]
Net Sales									1,620,054	1,288,824	1,270,978
Costs and expenses:
Cost of sales and operating expenses									1,330,038	988,295	949,534
Selling, general and administrative expense									54,070	76,016	71,141
Depreciation and amortization									83,957	68,139	61,807
Business Combination, Acquisition and Integration Related Costs									0	0
Total costs and expenses									1,468,065	1,132,450	1,082,482
Operating income									151,989	156,374	188,496
Interest expense									21,231	3,281	(7)
Foreign currency gains (losses)									(417)	(42)
Other income/(expense), net									(19)	55	3,355
Equity in net income of unconsolidated subsidiaries									0	0	0
Earnings in investments in subsidiaries									0	0	0
Income from operations before income taxes									172,784	159,668	191,844
Income taxes (benefit)									17,534	52,351	70,523
Net Income (Loss) Attributable to Noncontrolling Interest									0
Net income attributable to Darling									155,250	107,317	121,321
Non-guarantors [Member]
Net Sales									2,063,310	41,196	14,874
Costs and expenses:
Cost of sales and operating expenses									1,655,487	28,325	14,191
Selling, general and administrative expense									175,252	3,086	140
Depreciation and amortization									154,377	5,854	22
Business Combination, Acquisition and Integration Related Costs									4,257	9,197
Total costs and expenses									1,989,373	46,462	14,353
Operating income									73,937	(5,266)	521
Interest expense									(58,554)	(4,425)	0
Foreign currency gains (losses)									(887)	633
Other income/(expense), net									3,854	(229)	(23)
Equity in net income of unconsolidated subsidiaries									65,609	7,660	(2,662)
Earnings in investments in subsidiaries									0	0	0
Income from operations before income taxes									83,959	(1,627)	(2,164)
Income taxes (benefit)									11,323	512	(796)
Net Income (Loss) Attributable to Noncontrolling Interest									(4,096)
Net income attributable to Darling									68,540	(2,139)	(1,368)
Eliminations [Member]
Net Sales									(284,237)	(235,918)	(192,732)
Costs and expenses:
Cost of sales and operating expenses									(284,237)	(235,918)	(192,732)
Selling, general and administrative expense									0	0	0
Depreciation and amortization									0	0	0
Business Combination, Acquisition and Integration Related Costs									0	0
Total costs and expenses									(284,237)	(235,918)	(192,732)
Operating income									0	0	0
Interest expense									(181)	0	0
Foreign currency gains (losses)									0	0
Other income/(expense), net									181	0	0
Equity in net income of unconsolidated subsidiaries									0	0	0
Earnings in investments in subsidiaries									(223,790)	(105,178)	(119,953)
Income from operations before income taxes									(223,790)	(105,178)	(119,953)
Income taxes (benefit)									0	0	0
Net Income (Loss) Attributable to Noncontrolling Interest									0
Net income attributable to Darling									$ (223,790)	$ (105,178)	$ (119,953)