Revenue Recognition - Contract Costs (Details) - USD ($) $ in Thousands |
3 Months Ended | ||
|---|---|---|---|
Mar. 31, 2019 |
Mar. 31, 2018 |
Dec. 31, 2018 |
|
| Capitalized Contract Cost [Line Items] | |||
| Contract cost amortization | $ 1,250 | $ 570 | |
| Capitalized contract cost, amortization period | 5 years | ||
| Bonuses and Commissions | |||
| Capitalized Contract Cost [Line Items] | |||
| Contract cost assets | $ 2,500 | $ 1,500 | |
| Contract cost amortization | 100 | ||
| Contract Fulfillment Costs | |||
| Capitalized Contract Cost [Line Items] | |||
| Contract cost assets | 20,000 | $ 17,600 | |
| Contract cost amortization | $ 1,200 | $ 500 | |