XML 175 R156.htm IDEA: XBRL DOCUMENT v3.10.0.1
Schedule II - Valuation and Qualifying Accounts (Details) - USD ($)
$ in Thousands
12 Months Ended
Dec. 31, 2018
Dec. 31, 2017
Dec. 31, 2016
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]      
Balance at January 1 $ 6,869 $ 1,708 $ 1,786
Allowance for doubtful accounts 26,860 14,602 3,314
Charge-offs (19,155) (9,531) (3,316)
Effect of changes in foreign exchange rates (60) 90 (76)
Balance at December 31 $ 14,514 $ 6,869 $ 1,708