SHARE-BASED COMPENSATION - 2018 Plan (Details)	3 Months Ended
Mar. 31, 2020 shares
Share-Based Compensation Awards
Options granted (in shares)	717,000
2018 Plan
Share-Based Compensation Awards
Shares reserved for issuance pursuant to the plan	5,500,000
Annual increase on share reserve (as a percent)	4.00%
2018 Plan \| Stock options \| Employees and nonemployees owning less than 10% of voting power
Share-Based Compensation Awards
Term of award	10 years
Vesting period	4 years
2018 Plan \| Stock options \| Participants owning more than 10% of voting power
Share-Based Compensation Awards
Term of award	5 years
2018 Plan \| Stock options \| Participants owning more than 10% of voting power \| Minimum
Share-Based Compensation Awards
Ownership (as a percent)	10.00%
Option price as percentage of fair market value of common stock on the date of grant	110.00%

Aggregate number of common shares reserved for future issuance.

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