Equity Compensation (Expense) (Details) - USD ($)
$ in Thousands |
12 Months Ended |
Dec. 31, 2018 |
Dec. 31, 2017 |
Dec. 31, 2016 |
| Total stock-based compensation expense |
|
|
|
| Recognized tax benefits on total stock-based compensation expense |
$ 10,100
|
$ 600
|
$ 100
|
| Recognized tax benefits from stock option awards exercised |
4,500
|
|
|
| Stock options |
|
|
|
| Total stock-based compensation expense |
|
|
|
| Total stock-based compensation expense |
13,511
|
12,105
|
8,370
|
| Total unrecognized compensation cost related to non-vested stock option awards |
$ 700
|
|
|
| Weighted-average period over which unrecognized compensation cost will be recognized |
4 months 24 days
|
|
|
| Stock options | Cost of revenue |
|
|
|
| Total stock-based compensation expense |
|
|
|
| Total stock-based compensation expense |
$ 247
|
251
|
171
|
| Stock options | Research and development |
|
|
|
| Total stock-based compensation expense |
|
|
|
| Total stock-based compensation expense |
4,379
|
4,242
|
3,256
|
| Stock options | Sales and marketing |
|
|
|
| Total stock-based compensation expense |
|
|
|
| Total stock-based compensation expense |
3,770
|
3,662
|
2,273
|
| Stock options | General and administrative |
|
|
|
| Total stock-based compensation expense |
|
|
|
| Total stock-based compensation expense |
5,115
|
$ 3,950
|
$ 2,670
|
| Restricted stock units |
|
|
|
| Total stock-based compensation expense |
|
|
|
| Total unrecognized compensation cost related to non-vested stock option awards |
$ 10,500
|
|
|
| Weighted-average period over which unrecognized compensation cost will be recognized |
1 year 8 months 12 days
|
|
|