Condensed Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands |
Mar. 31, 2018 |
Dec. 31, 2017 |
|---|---|---|
| Statement of Financial Position [Abstract] | ||
| Accounts receivable, allowance for doubtful accounts | $ 699 | $ 634 |
| Preferred stock, par value | $ 0.001 | $ 0.001 |
| Preferred stock, shares authorized | 10,000,000 | 10,000,000 |
| Preferred stock, shares issued | 0 | 0 |
| Preferred stock, shares outstanding | 0 | 0 |
| Common stock, par value | $ 0.001 | $ 0.001 |
| Common stock, shares authorized | 250,000,000 | 250,000,000 |
| Common stock, shares issued | 45,587,983 | 44,934,364 |
| Treasury stock, shares | 3,419,116 | 3,215,644 |