Reconciliation of Changes in Benefit Obligation and Fair Value of Plan Assets and Unfunded Status of Plan (Detail) (USD $)	12 Months Ended
	Dec. 29, 2012	Dec. 31, 2011	Dec. 25, 2010
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 148,000	$ 163,000	$ 175,000
Interest cost	4,866,000	5,301,000	5,291,000
Benefit payments	(3,785,000)	(3,146,000)	(2,626,000)
Current liability	4,300,000	4,029,000
Noncurrent liability	116,721,000	103,595,000
Total recognized liability	121,021,000	107,624,000
Change in Benefit Obligation
Defined Benefit Plan Disclosure [Line Items]
Benefit obligation as of beginning of year	107,624,000	94,776,000
Service cost	148,000	163,000
Interest cost	4,866,000	5,301,000
Actuarial loss	12,168,000	10,530,000
Benefit payments	(3,785,000)	(3,146,000)
Benefit obligation as of end of year	121,021,000	107,624,000
Change in Fair Value of Plan Assets
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets as of beginning of year
Employer contributions	3,785,000	3,146,000
Benefit payments	(3,785,000)	(3,146,000)
Fair value of plan assets as of end of year
Unfunded status of the plan as of end of year	$ 121,021,000	$ 107,624,000