Table:
Year Ended December 31,

2019	2018	2017

Cost of revenues	2,193	2,315	2,000

Sales and marketing	6,812	6,596	6,621

Research and development	4,804	6,137	7,949

General and administrative	18,328	16,338	15,682

Total stock-based compensation expense	32,137	31,386	32,252

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|  |  | Year Ended December 31, |  |
| --- | --- | --- | --- |
|  | 2019 | 2018 | 2017 |
| Cost of revenues | 2,193 | 2,315 | 2,000 |
| Sales and marketing | 6,812 | 6,596 | 6,621 |
| Research and development | 4,804 | 6,137 | 7,949 |
| General and administrative | 18,328 | 16,338 | 15,682 |
| Total stock-based compensation expense | 32,137 | 31,386 | 32,252 |