Employee Benefit Plans (Details) (USD $)	9 Months Ended				9 Months Ended	3 Months Ended		9 Months Ended		3 Months Ended		9 Months Ended
	Sep. 27, 2014 plan	Sep. 28, 2013	Jan. 01, 2011	Jan. 03, 2009	Sep. 27, 2014 Maximum [Member]	Sep. 27, 2014 Other Postretirement Benefit Plan, Defined Benefit [Member]	Sep. 28, 2013 Other Postretirement Benefit Plan, Defined Benefit [Member]	Sep. 27, 2014 Other Postretirement Benefit Plan, Defined Benefit [Member]	Sep. 28, 2013 Other Postretirement Benefit Plan, Defined Benefit [Member]	Sep. 27, 2014 Pension Plan, Defined Benefit [Member]	Sep. 28, 2013 Pension Plan, Defined Benefit [Member]	Sep. 27, 2014 Pension Plan, Defined Benefit [Member]	Sep. 28, 2013 Pension Plan, Defined Benefit [Member]	Jan. 07, 2014 Vion Ingredients [Member]
Defined Benefit Plan Disclosure [Line Items]
Business combination, pension and postretirement benefit plan obligations assumed														$ 31,300,000
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract]
Service cost						43,000	0	131,000	0	1,418,000	77,000	4,316,000	230,000
Interest cost						20,000	0	62,000	0	3,275,000	1,318,000	9,934,000	3,954,000
Expected return on plan assets										(3,563,000)	(1,819,000)	(10,782,000)	(5,457,000)
Amortization of prior service cost										4,000	15,000	12,000	45,000
Amortization of net loss										520,000	1,300,000	1,559,000	3,900,000
Net pension cost						63,000	0	193,000	0	1,654,000	891,000	5,039,000	2,672,000
Amount Company expects to contribute to its pension plans	6,100,000
Pension Contributions	4,700,000	4,000,000
Multiemployer Plans [Abstract]
Multiemployer Plan, Contributions To Individual Plan, Percent					5.00%
Number Of Multiemployer Plans, Withdrawal Obligation Could Be Material	2
Number Of Multiemployer Plans Withdrawal Obligation Could Be Material Certified Red Zone	1
Number of Multiemployer Plans, Certified Red Zone	4
Number of Multiemployer Plans, Certified Yellow Zone	2
Number of Multiemployer Plans, Certified Orange Zone	1
Accrued liability representing the present value of scheduled withdrawal liability payments for under-funded multi-employer plan	$ 800,000		$ 1,200,000	$ 3,200,000