Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	12 Months Ended
	Dec. 27, 2017	Dec. 28, 2016	Dec. 30, 2015
Statement of Comprehensive Income [Abstract]
Net income	$ 39,594	$ 19,402	$ 35,976
Other comprehensive income (loss), net of tax:
Minimum pension liability adjustment, net of tax of $(22), $2,148 and $1,425	(37)	21,819	2,230
Recognition of unrealized gain (loss) on hedge transactions, net of tax of $(559), $353 and $(898)	(872)	551	(1,405)
Other comprehensive (loss) income	(909)	22,370	825
Total comprehensive income	$ 38,685	$ 41,772	$ 36,801