Supplemental Stockholders' Equity Information Reclassifications Out of Accumulated Other Comprehensive Income (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 26, 2017	Mar. 27, 2016
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Income tax expense	$ 3,531	$ 3,103
Accumulated Defined Benefit Plans Adjustment
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Income tax expense	2,736
Accumulated Defined Benefit Plans Adjustment | Reclassification out of Accumulated Other Comprehensive Income
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Total reclassification, before tax	6,921
Income tax expense	2,736
Total reclassification, net of tax	4,185
Selling, General and Administrative Expenses | Accumulated Defined Benefit Plans Adjustment | Reclassification out of Accumulated Other Comprehensive Income
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Amortization of prior service credit	(2,425)
Amortization of actuarial loss	$ 9,346