SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Allowance for Doubtful Accounts (Details) - USD ($) $ in Thousands |
12 Months Ended | ||
|---|---|---|---|
Jun. 30, 2020 |
Jun. 30, 2019 |
Jun. 30, 2018 |
|
| Allowance for Doubtful Accounts Receivable [Roll Forward] | |||
| Beginning balance | $ 203 | $ 453 | $ 440 |
| Charged to (released from) expenses | 85 | (250) | 13 |
| Bad debt write-offs | (85) | 0 | 0 |
| Ending balance | $ 203 | $ 203 | $ 453 |