Investment in Unconsolidated Subsidiary (Revenues and Expenses) (Details) - USD ($) $ in Thousands	3 Months Ended						6 Months Ended
	Jul. 03, 2021	Jun. 30, 2021	Apr. 03, 2021	Jun. 30, 2020	Jun. 27, 2020	Mar. 28, 2020	Jul. 03, 2021	Jun. 30, 2021	Jun. 30, 2020	Jun. 27, 2020
Revenues:
Operating revenues	$ 1,198,669				$ 848,673		$ 2,245,385			$ 1,701,515
Expenses:
Cost of sales and operating expenses	878,073				632,347		1,650,857			1,279,255
Total costs and expenses	1,056,199				805,877		2,005,629			1,633,710
Operating income	268,258				106,288		467,769			229,117
Net income	$ 198,069		$ 153,418		$ 66,495	$ 86,091	$ 351,487			$ 152,586
Diamond Green Diesel Holdings LLC Joint Venture [Member] | Equity Method Investment, Nonconsolidated Investee or Group of Investees
Revenues:
Operating revenues		$ 571,859		$ 295,826				$ 1,003,492	$ 654,441
Expenses:
Cost of sales and operating expenses		307,857		157,611				523,091	308,958
Depreciation, amortization and accretion expense		11,995		11,114				23,682	22,888
Total costs and expenses		319,852		168,725				546,773	331,846
Operating income		252,007		127,101				456,719	322,595
Other income		353		200				411	661
Interest and debt expense, net		(784)		(317)				(1,104)	(632)
Net income		$ 251,576		$ 126,984				$ 456,026	$ 322,624