Annual report pursuant to Section 13 and 15(d)

Revenue - Allowance for Doubtful Accounts (Details)

v3.19.1
Revenue - Allowance for Doubtful Accounts (Details) - USD ($)
$ in Thousands
12 Months Ended
Dec. 31, 2018
Dec. 31, 2017
Dec. 31, 2016
Allowance for Doubtful Accounts Receivable [Roll Forward]      
Beginning balance $ 8,680 $ 10,091 $ 8,640
Additions charged to statements of operations 1,227 2,788 2,624
Less: Bad debt write offs (4,229) (4,199) (1,173)
Ending balance $ 5,678 $ 8,680 $ 10,091