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Segment Information and Foreign Operations - Concentration of Credit Risk (Details) - customer
3 Months Ended 12 Months Ended
Mar. 31, 2017
Mar. 31, 2016
Dec. 31, 2016
Revenue [Member]      
Revenue, Major Customer [Line Items]      
Number of customers representing significant share 1 1  
Accounts Receivable [Member]      
Revenue, Major Customer [Line Items]      
Number of customers representing significant share 1   1
IQE Group Customer [Member] | Revenue [Member]      
Revenue, Major Customer [Line Items]      
Percentage share generated by major customers   12.00%  
Osram Opto [Member] | Revenue [Member]      
Revenue, Major Customer [Line Items]      
Percentage share generated by major customers 11.00%    
Major Customer One [Member] | Accounts Receivable [Member]      
Revenue, Major Customer [Line Items]      
Percentage share generated by major customers 12.00%   13.00%
Top Five Major Customers [Member] | Revenue [Member]      
Revenue, Major Customer [Line Items]      
Number of customers representing significant share 5 5  
Percentage share generated by major customers 35.00% 41.00%