Income Taxes (Details) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2018	Jul. 01, 2017	Dec. 31, 2017
Income Tax Disclosure [Abstract]
Effective income tax rate	18.20%	39.20%
Income tax liability, transition toll tax	$ 6,100
Unrecognized tax benefits	1,034		$ 2,581
Unrecognized tax benefits that would impact effective tax rate	561		1,948
Unrecognized tax benefits, interest on income taxes accrued	$ 21		$ 128