Other Comprehensive Earnings (Loss), Reclassification From Accumulated Other Comprehensive Loss (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Oct. 01, 2017	Sep. 30, 2018	Oct. 01, 2017
Reclassification Adjustment out of Accumulated Other Comprehensive Income (Loss) [Line Items]
Interest Expense	$ 22,779	$ 25,072	$ 68,391	$ 73,752
Reclassification out of Accumulated Other Comprehensive Income [Member] | Gains (Losses) On Derivative Instruments [Member] | Interest Rate Contract [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income (Loss) [Line Items]
Interest Expense	$ 450	$ 450	$ 1,349	$ 1,383