Retirement Plans (Details) (USD $)	3 Months Ended		6 Months Ended
	Jul. 03, 2011	Jul. 04, 2010	Jul. 03, 2011	Jul. 04, 2010
Discretionary contributions to the U.S. qualified pension plan			$ 4,400,000
Net Periodic Pension Cost [Member]
Service cost	668,000	921,000	1,493,000	1,952,000
Interest cost	4,459,000	4,268,000	8,849,000	8,816,000
Expected return on plan assets	(4,187,000)	(5,273,000)	(8,375,000)	(10,140,000)
Prior service cost	155,000	181,000	310,000	363,000
Net loss	2,341,000	1,022,000	4,386,000	2,768,000
Settlement	935,000		935,000
Total net periodic pension cost	4,371,000	1,119,000	7,598,000	3,759,000
Net Periodic Post-Retirement Cost [Member]
Service cost	14,000	7,000	30,000	27,000
Interest cost	134,000	174,000	269,000	392,000
Prior service cost	(150,000)	(59,000)	(299,000)	(117,000)
Net loss	45,000	(25,000)	90,000	29,000
Total net periodic pension cost	$ 43,000	$ 97,000	$ 90,000	$ 331,000