Supplemental Cash Flow Information (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 29, 2016	Mar. 31, 2015
Supplemental Cash Flow Information [Abstract]
Stock Repurchased and Retired During Period, Accrued	$ 7,465	$ 0
Interest Paid	1,496	298
Income Taxes Paid	6,621	4,044
Change in Accrued Capital Expenditures	(12,035)	(2,051)
Asset Retirement Obligation	$ 333	$ 91