Annual report pursuant to Section 13 and 15(d)

Valuation and qualifying accounts (Details)

v3.20.4
Valuation and qualifying accounts (Details) - USD ($)
$ in Thousands
12 Months Ended
Dec. 31, 2020
Dec. 31, 2019
Dec. 31, 2018
Allowance for doubtful accounts      
Valuation and qualifying accounts      
Balance at the beginning of the year $ 1,487 $ 871 $ 1,056
Additions charged to earnings 1,081 1,361 531
Changes to net 361 (745) (716)
Balance at the end of the year 2,929 1,487 871
Valuation of deferred tax assets      
Valuation and qualifying accounts      
Balance at the beginning of the year 1,612 1,473 777
Changes to net 1,762 139 696
Balance at the end of the year $ 3,374 $ 1,612 $ 1,473