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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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RELATED PARTY TRANSACTIONS (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Director \| Protoden Intellectual Property
Related Party Transaction [Line Items]
Amount of related party transaction			$ 0.1	$ 0.1
Annual fee under license agreement			0.1
Majority Shareholder \| Rent Expense Associated With Lease [Member]
Related Party Transaction [Line Items]
Amount of related party transaction	$ 0.1	$ 0.1	$ 0.1	$ 0.1