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Long-Term Debt Schedule of Long-Term Debt (Details) - USD ($) $ in Thousands	Sep. 29, 2018	May 31, 2018	Dec. 30, 2017
Debt Instrument [Line Items]
Total debt	$ 250,054		$ 276,648
Deferred debt issuance costs	(666)		0
Current maturities of long-term debt	720		36,648
Long-term debt	$ 249,334		$ 240,000
Revolving credit facility with interest at a variable rate (September 29, 2018 - 3.4%; December 30, 2017 - 2.7%)
Debt Instrument [Line Items]
Interest rate	3.40%		2.70%
Total debt	$ 150,000		$ 267,500
Fixed rate notes due in 2025 with an interest rate of 4.22%
Debt Instrument [Line Items]
Total debt	50,000		0
Fixed rate notes due in 2028 with an interest rate of 4.40%
Debt Instrument [Line Items]
Total debt	50,000		0
Other amounts
Debt Instrument [Line Items]
Total debt	$ 720		$ 9,148
Fixed rate notes due in 2025 with an interest rate of 4.22%
Debt Instrument [Line Items]
Interest rate	4.22%	4.22%
Fixed rate notes due in 2028 with an interest rate of 4.40%
Debt Instrument [Line Items]
Interest rate	4.40%	4.40%