Long-Term Debt Schedule of Long-Term Debt (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 30, 2017
Debt Instrument [Line Items]
Total debt	$ 328,964	$ 276,648
Current maturities of long-term debt	78,964	36,648
Long-term debt	250,000	240,000
Revolving credit facility with interest at a variable rate (March 31, 2018 - 3.0%; December 30, 2017 - 2.7%)
Debt Instrument [Line Items]
Total debt	$ 328,000	$ 267,500
Stated Interest Rate Percentage	3.00%	2.70%
Other amounts
Debt Instrument [Line Items]
Total debt	$ 964	$ 9,148