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EQUITY-BASED COMPENSATION - Narrative (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020	Dec. 31, 2019	Jul. 19, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares outstanding	1,603,972	338,233	1,563,972	166,233
Number of stock options granted (shares)	40,000	182,000
Fair value	$ 0.1	$ 0.1
Unrecognized compensation cost, options	$ 1.3	$ 0.5
Unrecognized compensation cost, recognition period	2 years 10 months 24 days
Flex Pharma
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares outstanding	34,385				90,279
Employee stock option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options, contractual term	10 years
Minimum \| Employee stock option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	1 year
Maximum \| Employee stock option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	4 years
2015 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares remaining available for grant of stock awards (shares)	1,020,690