Pension and Other Postretirement Benefits (Details) (USD $)	0 Months Ended	3 Months Ended			9 Months Ended
	Apr. 25, 2014	Sep. 28, 2014	Jun. 29, 2014	Sep. 29, 2013	Sep. 28, 2014	Sep. 29, 2013	Apr. 25, 2014
Defined Benefit Plan Disclosure [Line Items]
Pension withdrawal expense		$ 0		$ 6,171,000	$ 0	$ 6,171,000
Pension plan, estimated settlement charge		0	9,500,000	0	9,525,000	0
Liabilities settled							32,000,000
Net periodic benefit cost/(income)
Effect of settlement	24,000,000				9,500,000
Other Postretirement Benefit Changes [Abstract]
Unrecognized (gain)/loss due to change in discount rate		3,600,000
Unrecognized prior service cost due to change in plan provisions		(17,400,000)
Total effect of other postretirement benefit changes		(13,800,000)
Estimated increase in liability due to new guidance		150,000,000			150,000,000
Estimated increase in expense due to new guidance		10,000,000			10,000,000
Qualified Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Contributions to certain qualified pension plans					12,000,000
Expected additional contributions for the year					1,900,000
Net periodic benefit cost/(income)
Service cost		2,386,000		2,323,000	7,158,000	6,968,000
Interest cost		21,112,000		19,284,000	63,336,000	57,858,000
Expected return on plan assets		(28,460,000)		(31,063,000)	(85,380,000)	(93,188,000)
Amortization of prior service credit		(486,000)		(486,000)	(1,456,000)	(1,459,000)
Amortization of actuarial loss		6,655,000		8,443,000	19,964,000	25,327,000
Effect of settlement					0	0
Net periodic benefit cost/(income)		1,207,000		(1,499,000)	3,622,000	(4,494,000)
Non-Qualified Plans [Member]
Net periodic benefit cost/(income)
Service cost		0		256,000	0	768,000
Interest cost		2,382,000		2,643,000	7,968,000	7,929,000
Expected return on plan assets		0		0	0	0
Amortization of prior service credit		0		0	0	0
Amortization of actuarial loss		990,000		1,313,000	3,077,000	3,935,000
Effect of settlement					9,525,000	0
Net periodic benefit cost/(income)		3,372,000		4,212,000	20,570,000	12,632,000
Pension Plans, Defined Benefit [Member]
Net periodic benefit cost/(income)
Service cost		2,386,000		2,579,000	7,158,000	7,736,000
Interest cost		23,494,000		21,927,000	71,304,000	65,787,000
Expected return on plan assets		(28,460,000)		(31,063,000)	(85,380,000)	(93,188,000)
Amortization of prior service credit		(486,000)		(486,000)	(1,456,000)	(1,459,000)
Amortization of actuarial loss		7,645,000		9,756,000	23,041,000	29,262,000
Effect of settlement					9,525,000	0
Net periodic benefit cost/(income)		4,579,000		2,713,000	24,192,000	8,138,000
Other Postretirement Benefit Plan, Defined Benefit [Member]
Net periodic benefit cost/(income)
Service cost		145,000		285,000	439,000	855,000
Interest cost		930,000		1,009,000	2,950,000	3,027,000
Amortization of prior service credit		(1,800,000)		(3,693,000)	(5,000,000)	(11,078,000)
Amortization of actuarial loss		1,237,000		1,022,000	3,605,000	3,066,000
Net periodic benefit cost/(income)		512,000		(1,377,000)	1,994,000	(4,130,000)
Other Postretirement Benefit Changes [Abstract]
Unrecognized (gain)/loss due to change in discount rate		3,617,000		0	3,617,000	0
Unrecognized prior service cost due to change in plan provisions		(17,373,000)		0	(17,373,000)	0
Total effect of other postretirement benefit changes		$ (13,756,000)		$ 0	$ (13,756,000)	$ 0