Income Taxes (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Oct. 01, 2016	Oct. 03, 2015	Oct. 01, 2016	Oct. 03, 2015
Deferred:
Income tax expense	$ 1,344	$ 467	$ 3,319	$ 2,112
Effective income tax rate reconciliation
Effective income tax rate (as a percent)	6.30%	4.50%	7.40%	8.10%
Components of deferred taxes
Gross unrecognized tax benefits	$ 3,900		$ 3,900
Gross unrecognized tax benefits which would affect the effective tax rate if recognized	3,000		3,000
Accrual for the payment of interest related to unrecognized tax positions	100		100
Amount of estimated decrease in unrecognized tax benefits	$ 1,200		1,200
Maximum
Components of deferred taxes
Interest in the provision for income taxes recognized			$ 100	$ 100