STOCK-BASED COMPENSATION - General and ESPP (Details) - USD ($)
|
12 Months Ended |
Dec. 31, 2021 |
Dec. 31, 2020 |
| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |
|
|
| Tax benefit on total stock-based compensation |
$ 0
|
$ 0
|
| Weighted-average grant date fair value of awards granted (in dollars per share) |
$ 1.11
|
$ 1.64
|
| Options exercised during period (in shares) |
72,750
|
0
|
| Issuance of common stock upon exercise of options |
$ 193,000
|
|
| Proceeds from exercise of stock options |
193,000
|
$ 0
|
| Restricted stock units |
|
|
| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |
|
|
| Unrecognized compensation expense, other than options |
$ 4,700,000
|
|
| Average vesting period for recognition of unrecognized compensation expense |
1 year 11 months 1 day
|
|
| Stock Options |
|
|
| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |
|
|
| Unrecognized compensation expense, options |
$ 2,300,000
|
|
| Average vesting period for recognition of unrecognized compensation expense |
2 years 10 months 28 days
|
|
| Issuance of common stock upon exercise of options |
$ 100,000
|
|
| Total fair value of options vested |
$ 200,000
|
$ 700,000
|
| ESPP |
|
|
| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |
|
|
| Weighted-average grant date fair value (in dollars per share) |
|
$ 1.64
|