Annual report pursuant to Section 13 and 15(d)

Business Segments and Customer Information - Geographic Area (Details)

v3.20.4
Business Segments and Customer Information - Geographic Area (Details) - USD ($)
$ in Thousands
 3 Months Ended 12 Months Ended
Dec. 31, 2020
Sep. 30, 2020
Jun. 30, 2020
Mar. 31, 2020
Dec. 31, 2019
Sep. 30, 2019
Jun. 30, 2019
Mar. 31, 2019
Dec. 31, 2020
Dec. 31, 2019
Dec. 31, 2018
Revenues from External Customers and Long-Lived Assets [Line Items]                      
Revenues $ 150,021 $ 165,505 $ 168,715 $ 177,418 $ 195,271 $ 198,326 $ 189,111 $ 169,919 $ 661,659 $ 752,627 $ 697,218
United States                      
Revenues from External Customers and Long-Lived Assets [Line Items]                      
Revenues                 598,142 659,451 647,168
Other Countries                      
Revenues from External Customers and Long-Lived Assets [Line Items]                      
Revenues                 $ 63,517 $ 93,176 $ 50,050