SHARE-BASED COMPENSATION EXPENSE - Summary of Information about Non Vested Stock Options (Detail) shares in Thousands |
12 Months Ended |
|---|---|
|
Dec. 31, 2017
$ / shares
shares
| |
| Summary Of Information About Non Vested Stock Options Disclosure [Line Items] | |
| Outstanding, beginning | shares | 335 |
| Granted | shares | 185 |
| Vested | shares | (236) |
| Forfeited | shares | (14) |
| Outstanding, ending | shares | 270 |
| Outstanding beginning, Weighted Average Fair Value | $ / shares | $ 1.18 |
| Granted, Weighted Average Fair Value | $ / shares | 0.45 |
| Vested, Weighted Average Fair Value | $ / shares | 1.34 |
| Forfeited, Weighted Average Fair Value | $ / shares | 1.05 |
| Outstanding ending, Weighted Average Fair Value | $ / shares | $ 0.46 |