Annual report pursuant to Section 13 and 15(d)

Item 15 (Details)

v3.19.3.a.u2
Item 15 (Details) - USD ($)
$ in Thousands
 12 Months Ended
Dec. 31, 2019
Dec. 31, 2018
Dec. 31, 2017
Dec. 31, 2016
SEC Schedule, 12-09, Allowance, Credit Loss [Member]        
SEC Schedule, 12-09, Valuation and Qualifying Accounts Disclosure [Line Items]        
Allowances for Doubtful Accounts $ 0 $ 46 $ 73 $ 87
SEC Schedule, 12-09, Valuation Allowances and Reserves, Additions, Charge to Cost and Expense 0 0 133  
SEC Schedule, 12-09, Valuation Allowances and Reserves, Additions, Charge to Other Account 0 0 27  
SEC Schedule, 12-09, Valuation Allowances and Reserves, Deduction (46) (27) (174)  
SEC Schedule, 12-09, Reserve, Warranty [Member]        
SEC Schedule, 12-09, Valuation and Qualifying Accounts Disclosure [Line Items]        
Allowances for Doubtful Accounts 553 519 941 860
SEC Schedule, 12-09, Valuation Allowances and Reserves, Additions, Charge to Cost and Expense 74 (414) 492  
SEC Schedule, 12-09, Valuation Allowances and Reserves, Additions, Charge to Other Account 0 0 122  
SEC Schedule, 12-09, Valuation Allowances and Reserves, Deduction (40) (8) (533)  
SEC Schedule, 12-09, Valuation Allowance, Deferred Tax Asset [Member]        
SEC Schedule, 12-09, Valuation and Qualifying Accounts Disclosure [Line Items]        
Allowances for Doubtful Accounts 77,957 79,196 84,560 $ 100,284
SEC Schedule, 12-09, Valuation Allowances and Reserves, Additions, Charge to Cost and Expense (1,239) (5,761) (50,881)  
SEC Schedule, 12-09, Valuation Allowances and Reserves, Additions, Charge to Other Account 0 397 35,157  
SEC Schedule, 12-09, Valuation Allowances and Reserves, Deduction $ 0 $ 0 $ 0