CONSOLIDATED BALANCE SHEETS (Parenthetical) - $ / shares |
Dec. 31, 2015 |
Dec. 31, 2014 |
|---|---|---|
| Statement Of Financial Position [Abstract] | ||
| Common stock, par value | $ 0.01 | $ 0.01 |
| Common stock, authorized | 240,000,000 | 240,000,000 |
| Common stock, shares issued | 115,900,000 | 115,900,000 |