CONDENSED CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($)	Dec. 31, 2016	Dec. 26, 2015
Statement of Financial Position [Abstract]
Receivables, allowance for doubtful accounts	$ 10,250	$ 10,055
Other assets, allowance for doubtful accounts receivable	$ 8,741	$ 10,953
Preferred stock, par value (in dollars per share)	$ 1	$ 1
Preferred stock, authorized shares (in shares)	500,000	500,000
Preferred stock, issued shares (in shares)	0	0
Common stock, par value (in dollars per share)	$ 1	$ 1
Common stock, authorized shares (in shares)	75,000,000	75,000,000
Common stock, issued shares (in shares)	27,900,000	27,900,000
Common shares in treasury, shares	5,379,106	5,042,775