Share-based Compensation, Options (Details) - USD ($) $ / shares in Units, $ in Thousands	9 Months Ended
	Sep. 26, 2017	Sep. 27, 2016
Aggregate Intrinsic Value
Proceeds from exercise of stock options	$ 1,485	$ 2,172
Stock Options
Shares
Outstanding at the beginning of the period (in shares)	118,073
Cancelled/Expired (in shares)	(2,836)
Exercised (in shares)	(109,085)
Outstanding at the end of the period (in shares)	6,152
Exercisable at the end of period (in shares)	6,152
Stock options vested (in shares)	0	0
Weighted-Average Exercise Price
Outstanding at the beginning of the period (in dollars per share)	$ 13.57
Cancelled/Expired (in dollars per share)	15.47
Exercised (in dollars per share)	13.61
Outstanding at the end of the period (in dollars per share)	11.93
Exercisable at the end of the period (in dollars per share)	$ 11.93
Weighted-Average Remaining Contractual Term
Outstanding at the end of the period	1 month 6 days
Exercisable at the end of the period	1 month 6 days
Aggregate Intrinsic Value
Outstanding at the end of the period (in dollars)	$ 223
Exercisable at the end of the period (in dollars)	223
Intrinsic value of options exercised (in dollars)	3,700	$ 5,300
Proceeds from exercise of stock options	1,500	2,200
Excess tax benefit recognized within the income tax provision	$ 1,000
Excess tax benefit recorded in additional paid-in capital		$ 1,500