Annual report pursuant to Section 13 and 15(d)

Debt Debt - TOKIN Term Loan Facility (Details)

v3.19.1
Debt Debt - TOKIN Term Loan Facility (Details)
$ in Thousands, ¥ in Millions
12 Months Ended
Nov. 07, 2018
USD ($)
Nov. 07, 2018
JPY (¥)
Mar. 31, 2019
USD ($)
Mar. 31, 2019
JPY (¥)
Mar. 31, 2018
USD ($)
Mar. 31, 2017
USD ($)
Nov. 07, 2018
JPY (¥)
Debt Instrument [Line Items]              
Payment for Debt Extinguishment or Debt Prepayment Cost     $ 3,234   $ 0 $ 0  
Interest Payable, Current     211   396    
Term Loan Facility              
Debt Instrument [Line Items]              
Long-term Debt     $ 276,808   0    
Debt Instrument, Interest Rate, Effective Percentage     3.10%        
Term Loan Credit Agreement              
Debt Instrument [Line Items]              
Long-term Debt $ 323,400   $ 0   $ 318,782    
Debt, Prepayment Premium, Percent 1.00%           1.00%
Interest Payable, Current     $ 100        
Term Loan A Tranche | Term Loan Facility              
Debt Instrument [Line Items]              
Debt Instrument, Interest Rate, Stated Percentage 2.00%           2.00%
Term Loan B Tranche | Term Loan Facility              
Debt Instrument [Line Items]              
Debt Instrument, Interest Rate, Stated Percentage 2.25%           2.25%
Term Loan B Tranche | Term Loan Facility | TIBOR              
Debt Instrument [Line Items]              
Debt Instrument, Basis Spread on Variable Rate     0.13% 0.13%      
United States of America, Dollars | Term Loan Facility              
Debt Instrument [Line Items]              
Proceeds from Issuance of Secured Debt $ 283,900            
Net proceeds 281,800            
United States of America, Dollars | Term Loan A Tranche | Term Loan Facility              
Debt Instrument [Line Items]              
Long-term Debt 146,000            
Debt Instrument, Periodic Payment, Principal | ¥       ¥ 12.4      
United States of America, Dollars | Term Loan B Tranche | Term Loan Facility              
Debt Instrument [Line Items]              
Long-term Debt $ 146,000            
Japan, Yen | Term Loan Facility              
Debt Instrument [Line Items]              
Long-term Debt | ¥             ¥ 33,000.0
Proceeds from Issuance of Secured Debt | ¥   ¥ 32,100.0          
Japan, Yen | Term Loan A Tranche | Term Loan Facility              
Debt Instrument [Line Items]              
Long-term Debt | ¥             16,500.0
Debt Instrument, Periodic Payment, Principal | ¥       ¥ 1,400.0      
Japan, Yen | Term Loan B Tranche | Term Loan Facility              
Debt Instrument [Line Items]              
Long-term Debt | ¥             ¥ 16,500.0
Property, Plant and Equipment | Term Loan Facility              
Debt Instrument [Line Items]              
Debt Instrument, Collateral Amount     $ 50,600