Annual report pursuant to Section 13 and 15(d)

Segments - Schedule of Activities with Major Customers (Details)

v3.20.4
Segments - Schedule of Activities with Major Customers (Details)
$ in Thousands
 12 Months Ended
Dec. 31, 2020
USD ($)
customer
Dec. 31, 2019
USD ($)
Dec. 31, 2018
Segment Reporting [Abstract]      
Number of major customers | customer 2    
Boeing | Customer Concentration Risk | Consolidated Revenue      
Revenue, Major Customer      
Percent of consolidated revenue 9.50% 13.60% 14.30%
Boeing | Customer Concentration Risk | Accounts Receivable, Net      
Revenue, Major Customer      
Accounts receivable $ 6,490 $ 21,806  
Panasonic | Customer Concentration Risk | Consolidated Revenue      
Revenue, Major Customer      
Percent of consolidated revenue 11.10% 13.00% 14.40%
Panasonic | Customer Concentration Risk | Accounts Receivable, Net      
Revenue, Major Customer      
Accounts receivable $ 4,083 $ 15,831