FAIR VALUE MEASUREMENTS - Recurring Level III Assets (Details) - Level III - USD ($) $ in Thousands |
12 Months Ended | |
|---|---|---|
Dec. 31, 2016 |
Dec. 31, 2015 |
|
| Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] | ||
| Balance, beginning of period | $ 1,537 | $ 1,020 |
| Realized and unrealized gains included in earnings | 9 | 517 |
| Balance, end of period | $ 1,546 | $ 1,537 |