Note 7 - Retirement Plans (Detail) - Reconciliation of the changes in the Plans' benefit obligations: (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 25, 2011	Dec. 26, 2010
Change in benefit obligation:
Benefit Obligation, balance	$ 513,000	$ 455,000
Pension Plans, Defined Benefit [Member]
Change in benefit obligation:
Benefit Obligation, balance	454,904	412,135
Service cost			38
Interest cost	21,162	22,426	22,910
Actuarial loss (gain)	60,494	41,803
Benefit payments, net of subsidy	(23,658)	(21,460)
Benefit Obligation, balance	512,902	454,904	412,135
Other Pension Plans, Postretirement or Supplemental Plans, Defined Benefit [Member]
Change in benefit obligation:
Benefit Obligation, balance	39,599	42,160
Service cost	101	226	202
Interest cost	1,547	1,910	2,319
Participant contributions	1,462	1,450
Plan amendments	(3,518)
Actuarial loss (gain)	(812)	(2,155)
Benefit payments, net of subsidy	(3,758)	(3,992)
Curtailments	(7,183)
Benefit Obligation, balance	$ 27,438	$ 39,599	$ 42,160