CONSOLIDATED BALANCE SHEETS (Parenthetical) - $ / shares |
Dec. 31, 2016 |
Dec. 31, 2015 |
|---|---|---|
| Statement Of Financial Position [Abstract] | ||
| Preferred shares, par value | $ 0.01 | $ 0.01 |
| Preferred shares, authorized | 3,000,000 | 3,000,000 |
| Preferred shares, issued | 0 | 0 |
| Common stock, par value | $ 0.01 | $ 0.01 |
| Common stock, shares authorized | 30,000,000 | 30,000,000 |
| Common stock, shares issued | 17,819,538 | 17,567,154 |
| Common stock, shares outstanding | 17,819,538 | 17,567,154 |