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RELATED PARTY TRANSACTION (Details) - USD ($) $ in Millions		1 Months Ended	3 Months Ended		9 Months Ended		12 Months Ended
RELATED PARTY TRANSACTION (Details) - USD ($) $ in Millions	Nov. 30, 2017	Nov. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2018	Dec. 31, 2017	Jun. 30, 2018
RELATED PARTY TRANSACTIONS
Charges incurred			$ 0.1		$ 0.2
Prepaid expenses and other current assets \| Biomatrica
RELATED PARTY TRANSACTIONS
Amount loaned pursuant to a Senior Secured Promissory Note									$ 1.0
2017 Biomatrica Investment
RELATED PARTY TRANSACTIONS
Cash investment	$ 3.0	$ 3.0
Director \| Professional Services Agreement
RELATED PARTY TRANSACTIONS
Aggregate cash payments			0.2	$ 0.1	0.3	$ 0.2
Charges incurred			$ 0.2	$ 0.1	$ 0.3	$ 0.2
Director \| Professional Services Agreement \| Maximum
RELATED PARTY TRANSACTIONS
Aggregate cash payments								$ 0.5
Director \| Professional Services Agreement \| Forecast \| Maximum
RELATED PARTY TRANSACTIONS
Aggregate cash payments							$ 0.5