Stock-Based Compensation - Summary of Non-vested Options Activity (Detail) - $ / shares |
9 Months Ended | |
---|---|---|
Feb. 28, 2017 |
Feb. 29, 2016 |
|
Disclosure of Compensation Related Costs, Share-based Payments [Abstract] | ||
Number of Shares, Non-vested options, Beginning balance | 225,000 | |
Number of Shares, Granted | 49,000 | 225,000 |
Number of Shares, Vested | (45,000) | |
Number of Shares, Non-vested options, Ending balance | 229,000 | 225,000 |
Weighted Average Grant-Date Fair Value, Non-vested options, Beginning balance | $ 2.19 | |
Weighted Average Grant-Date Fair Value, Granted | 7.58 | $ 2.19 |
Weighted Average Grant-Date Fair Value, Vested | 2.19 | |
Weighted Average Grant-Date Fair Value, Non-vested options, Ending balance | $ 3.34 | $ 2.19 |