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Long-Term Debt Schedule of Long-Term Debt (Details) - USD ($) $ in Thousands	May 31, 2018	Jun. 30, 2018	Dec. 30, 2017
Debt Instrument [Line Items]
Total debt		$ 296,831	$ 276,648
Deferred debt issuance costs		(687)	0
Current maturities of long-term debt		434	36,648
Long-term debt		$ 296,397	$ 240,000
Revolving credit facility with interest at a variable rate (June 30, 2018 - 3.3%; December 30, 2017 - 2.7%)
Debt Instrument [Line Items]
Stated Interest Rate Percentage		3.30%	2.70%
Total debt		$ 197,000	$ 267,500
Seven-year fixed rate notes with an interest rate of 4.22%
Debt Instrument [Line Items]
Total debt		50,000	0
Ten-year fixed rate notes with an interest rate of 4.40%
Debt Instrument [Line Items]
Total debt		50,000	0
Other amounts
Debt Instrument [Line Items]
Total debt		$ 518	$ 9,148
Ten-year fixed rate notes with an interest rate of 4.40%
Debt Instrument [Line Items]
Stated Interest Rate Percentage	4.40%
Note term	10 years
Seven-year fixed rate notes with an interest rate of 4.22%
Debt Instrument [Line Items]
Stated Interest Rate Percentage	4.22%
Note term	7 years