Pension Benefits (Details) (USD $)	3 Months Ended		9 Months Ended
	Sep. 29, 2013	Sep. 23, 2012	Sep. 29, 2013	Sep. 23, 2012
Defined Benefit Pension Plans and Defined Benefit Postretirement Plans Disclosure [Abstract]
Service cost	$ 269,000	$ 207,000	$ 804,000	$ 637,000
Interest cost	883,000	940,000	2,631,000	2,898,000
Expected return on plan assets	26,000	10,000	77,000	31,000
Amortization of actuarial loss	390,000	54,000	1,165,000	166,000
Amortization of transition obligation	0	13,000	0	42,000
Amortization of prior service costs	1,000	1,000	2,000	2,000
Net periodic pension cost	1,569,000	1,225,000	4,679,000	3,776,000
Estimated employer contributions	5,300,000		5,300,000
Pension contributions			$ 4,200,000