Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Dec. 30, 2017	Dec. 31, 2016
Statement Of Financial Position [Abstract]
Allowance for doubtful accounts and customer credits	$ 97,193	$ 99,995
Common stock, par value	$ 0.01	$ 0.01
Common stock, shares authorized	50,000,000	50,000,000
Common stock, shares issued	33,571,524	34,517,633
Common stock, shares outstanding	33,571,524	34,517,633