Revenue from Contracts with Customers (Disaggregation of Revenue) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Apr. 01, 2017
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	$ 98,623	$ 104,587
Asia
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	71,921	73,458
Europe
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	12,142	11,080
Total revenue
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	14,560	20,049
Product revenue - Distributors
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	85,957	74,080
Product revenue - Direct
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	9,152	18,589
Licensing and services revenue
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	$ 3,514	$ 11,918