Supplemental Cash Flow Information (Details) - USD ($)	9 Months Ended
	Sep. 27, 2016	Sep. 29, 2015
Supplemental Cash Flow Information [Abstract]
Interest Paid	$ 5,358,000	$ 1,783,000
Income Taxes Paid	49,914,000	72,519,000
Change in Accrued Capital Expenditures	(14,725,000)	13,764,000
Stock Repurchased and Retired During Period, Accrued	7,481,000	0
Promissory Note Received in Lieu of Cash	(4,482,000)	0
Noncash or Part Noncash Acquisition, Fixed Assets Acquired	0	12,680,000
Asset Retirement Obligation	$ 514,000	$ 348,000