Income Taxes (Narrative) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Apr. 01, 2016
Income Tax Disclosure [Abstract]
Effective income tax rate	(3.40%)	0.80%
Loss before provision (benefit) for income taxes	$ 4,195	$ 12,762
Discrete tax expense items	900
Share-based compensation expense related to ASU 2016-09 adoption	600
Unrecognized Tax Benefits	10,900
Significant Change in Unrecognized Tax Benefits is Reasonably Possible, Amount of Unrecorded Benefit	100
Unrecognized Tax Benefits that Would Impact Effective Tax Rate	$ 10,100