STOCK OPTIONS (Details) - USD ($)
$ in Thousands |
1 Months Ended |
6 Months Ended |
12 Months Ended |
|
|
Jan. 31, 2017 |
Dec. 31, 2016 |
Dec. 31, 2016 |
Dec. 31, 2016 |
Dec. 31, 2015 |
Dec. 31, 2014 |
Apr. 30, 2015 |
Mar. 31, 2015 |
| Stock options |
|
|
|
|
|
|
|
|
| Maximum aggregate number of shares reserved for issuance during term of employee stock purchase plan |
|
6,585,224
|
6,585,224
|
6,585,224
|
|
|
|
|
| Stock-based compensation |
|
|
|
$ 5,063
|
$ 4,666
|
$ 2,730
|
|
|
| Stock Options |
|
|
|
|
|
|
|
|
| Stock options |
|
|
|
|
|
|
|
|
| Options to purchase common stock outstanding |
|
3,193,785
|
3,193,785
|
3,193,785
|
3,253,310
|
|
|
|
| Granted (in shares) |
|
|
|
333,250
|
|
|
|
|
| Expected term |
|
|
|
10 years
|
|
|
|
|
| Vesting period |
|
|
|
48 months
|
|
|
|
|
| 2007 Plan |
|
|
|
|
|
|
|
|
| Stock options |
|
|
|
|
|
|
|
|
| Options to purchase common stock outstanding |
|
150,207
|
150,207
|
150,207
|
|
|
|
|
| Shares available for future grants |
|
0
|
0
|
0
|
|
|
|
|
| Expected term |
|
|
|
10 years
|
|
|
|
|
| 2010 Plan |
|
|
|
|
|
|
|
|
| Stock options |
|
|
|
|
|
|
|
|
| Options to purchase common stock outstanding |
|
1,821,487
|
1,821,487
|
1,821,487
|
|
|
|
|
| Shares available for future grants |
|
322,355
|
322,355
|
322,355
|
|
|
|
|
| Granted (in shares) |
|
|
0
|
|
|
|
|
|
| Expected term |
|
|
|
10 years
|
|
|
|
|
| 2015 Plan |
|
|
|
|
|
|
|
|
| Stock options |
|
|
|
|
|
|
|
|
| Options to purchase common stock outstanding |
|
1,222,085
|
1,222,085
|
1,222,085
|
|
|
|
|
| Shares authorized for issuance |
|
4,322,355
|
4,322,355
|
4,322,355
|
|
|
4,000,000
|
|
| Expected term |
|
|
|
10 years
|
|
|
|
|
| Employee Stock Purchase Plan |
|
|
|
|
|
|
|
|
| Stock options |
|
|
|
|
|
|
|
|
| Shares authorized for issuance |
|
|
|
|
|
|
|
187,500
|
| Percentage of outstanding shares reserved for future issuance |
|
|
|
1.00%
|
|
|
|
|
| Increase in shares of common stock reserved for issuance |
|
|
|
50,000
|
|
|
|
|
| Maximum aggregate number of shares reserved for issuance during term of employee stock purchase plan |
|
1,250,000
|
1,250,000
|
1,250,000
|
|
|
|
|
| Offering Period |
|
|
|
6 months
|
|
|
|
|
| Stock issued under ESPP (in shares) |
7,986
|
|
|
|
|
|
|
|
| Stock-based compensation |
|
|
|
$ 46
|
$ 41
|
|
|
|
| Common Stock |
|
|
|
|
|
|
|
|
| Stock options |
|
|
|
|
|
|
|
|
| Stock issued under ESPP (in shares) |
|
|
|
16,729
|
|
|
|
|
| Accrued expenses. | Employee Stock Purchase Plan |
|
|
|
|
|
|
|
|
| Stock options |
|
|
|
|
|
|
|
|
| Employee payroll deductions |
|
$ 51
|
|
|
|
|
|
|