Annual report pursuant to Section 13 and 15(d)

Organization and Significant Accounting Policies - Concentrations of Credit and Other Risk (Details)

v3.20.1
Organization and Significant Accounting Policies - Concentrations of Credit and Other Risk (Details)
$ in Thousands
3 Months Ended 12 Months Ended
Mar. 31, 2020
USD ($)
Dec. 31, 2019
USD ($)
Sep. 30, 2019
USD ($)
Jun. 30, 2019
USD ($)
Mar. 31, 2019
USD ($)
Dec. 31, 2018
USD ($)
Sep. 30, 2018
USD ($)
Jun. 30, 2018
USD ($)
Mar. 31, 2020
USD ($)
Mar. 31, 2019
USD ($)
Mar. 31, 2018
USD ($)
Concentration Risk [Line Items]                      
Net sales $ 293,174 $ 294,741 $ 327,397 $ 345,242 $ 355,794 $ 350,175 $ 349,233 $ 327,616 $ 1,260,554 $ 1,382,818 $ 1,200,181
Accounts receivable | Credit risk                      
Concentration Risk [Line Items]                      
Number of Customers, Concentration Risk, Receivables 0       0       0 0  
Concentration risk, percentage                 10.00% 10.00%  
Revenue from Contract with Customer, Product and Service Benchmark [Member] | Electronics distributor risk                      
Concentration Risk [Line Items]                      
Concentration risk, percentage                 40.40% 42.20% 39.20%
Revenue from Contract with Customer, Product and Service Benchmark [Member] | Electronics distributor risk | TTI, Inc.                      
Concentration Risk [Line Items]                      
Number of Customers, Concentration Risk                 1    
Net sales                 $ 154,600 $ 184,300 $ 133,500