Revenue Recognition - Contract Acquisition Costs (Details) - USD ($) $ in Thousands |
9 Months Ended | |
|---|---|---|
Sep. 30, 2020 |
Sep. 30, 2019 |
|
| Increase (Decrease) In Capitalized Contract Cost [Roll Forward] | ||
| Balance at beginning of period | $ 113,592 | $ 114,306 |
| Additions | 68,589 | 71,651 |
| Amortization expense | (75,429) | (72,412) |
| Foreign currency translation | (2,984) | (1,012) |
| Balance at end of period | $ 103,768 | $ 112,533 |