| Three Months Ended June 30, 2018 | Six Months Ended June 30, 2018 | |||||||||||||||
| 2018 | 2017 | 2018 | 2017 | |||||||||||||
| Basic: | ||||||||||||||||
| Net income | $ | 5,917 | $ | 2,261 | $ | 26,072 | $ | 17,579 | ||||||||
Weighted average number of common shares during the period (in thousands) | 41,600 | 41,368 | 41,531 | 41,268 | ||||||||||||
| Net income per share – basic | $ | 0.14 | $ | 0.05 | $ | 0.63 | $ | 0.43 | ||||||||
| Diluted: | ||||||||||||||||
| Net income | $ | 5,917 | $ | 2,261 | $ | 26,072 | $ | 17,579 | ||||||||
Weighted average number of common shares during the period | 41,600 | 41,368 | 41,531 | 41,268 | ||||||||||||
Weighted average number of common equivalent shares to reflect the dilutive effect of common stock equivalent securities: | ||||||||||||||||
| Stock options | 115 | 123 | 109 | 142 | ||||||||||||
Common stock units related to deferred compensation for employees | 25 | 29 | 25 | 29 | ||||||||||||
Restricted common stock units related to incentive compensation | (5 | ) | (27 | ) | (6 | ) | (23 | ) | ||||||||
Total common and common equivalent shares adjusted to calculate diluted earnings per share | 41,735 | 41,493 | 41,659 | 41,416 | ||||||||||||
| Net income per share – diluted | $ | 0.14 | $ | 0.05 | $ | 0.63 | $ | 0.42 | ||||||||
