Other Comprehensive Earnings (Loss), Tax Effects on Changes in Other Comprehensive Earnings (loss) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Oct. 01, 2017	Sep. 25, 2016	Oct. 01, 2017	Sep. 25, 2016
Other Comprehensive Earnings (Loss) [Abstract]
Tax benefit on cash flow hedging activities	$ 1,700	$ 1,420	$ 5,936	$ 9,423
Tax benefit (expense) on unrealized holding losses and gains	445	221	315	(547)
Reclassification Adjustment from AOCE, Tax (benefit) expense on cash flow hedging activities	(1,875)	2,456	(2,884)	5,274
Reclassification Adjustment from AOCE, Tax benefit on amortization of unrecognized pension and postretirement amounts	(822)	(666)	(2,466)	(1,999)
Other Comprehensive (Loss) Income, Tax, Portion Attributable to Parent, Total	(552)	$ 3,431	$ 901	$ 12,151
Cash Flow Hedge gains to be Reclassified within Twelve Months	$ 18,932