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EQUITY-BASED COMPENSATION - Activity Related to Plans (Details) - USD ($) $ in Millions	1 Months Ended			12 Months Ended
	Feb. 28, 2019	Mar. 31, 2018	Feb. 28, 2017	Dec. 31, 2019
Stock Options
Beginning balance (shares)				3,716,579
Granted (shares)				1,061,587
Exercised (shares)				(2,025)
Expired or terminated (shares)				(890,324)
Ending balance (shares)				3,885,817
2019 Equity Plan
Stock Options
Beginning balance (shares)				0
Granted (shares)				479,212
Exercised (shares)				0
Expired or terminated (shares)				(6,800)
Ending balance (shares)				472,412
Restricted Stock Units
Remaining number of shares available for future grants (in shares)				2,828,030
2007 Equity Plan
Stock Options
Beginning balance (shares)				2,781,786
Granted (shares)				465,009
Exercised (shares)				(2,025)
Expired or terminated (shares)				(659,304)
Ending balance (shares)				2,585,466
Restricted Stock Units
Remaining number of shares available for future grants (in shares)				0
2013 Lumara Equity Plan
Stock Options
Beginning balance (shares)				124,450
Granted (shares)				37,000
Exercised (shares)				0
Expired or terminated (shares)				(29,675)
Ending balance (shares)				131,775
Restricted Stock Units
Remaining number of shares available for future grants (in shares)				9,817
Inducement Grants
Stock Options
Beginning balance (shares)				810,343
Granted (shares)				80,366
Exercised (shares)				0
Expired or terminated (shares)				(194,545)
Ending balance (shares)				696,164
RSUs
Restricted Stock Units
Outstanding at beginning of year (shares)				1,128,535
Granted (shares)				1,186,874
Vested (shares)				(404,305)
Expired or terminated (in shares)				(331,667)
Outstanding at end of year (shares)				1,579,437
Compensation expense, period for recognition				1 year 8 months 12 days
RSUs \| 2019 Equity Plan
Restricted Stock Units
Outstanding at beginning of year (shares)				0
Granted (shares)				132,542
Vested (shares)				0
Expired or terminated (in shares)				(3,800)
Outstanding at end of year (shares)				128,742
RSUs \| 2007 Equity Plan
Restricted Stock Units
Outstanding at beginning of year (shares)				1,041,141
Granted (shares)				1,023,847
Vested (shares)				(358,362)
Expired or terminated (in shares)				(299,321)
Outstanding at end of year (shares)				1,407,305
RSUs \| 2013 Lumara Equity Plan
Restricted Stock Units
Outstanding at beginning of year (shares)				2,101
Granted (shares)				1,100
Vested (shares)				(1,034)
Expired or terminated (in shares)				0
Outstanding at end of year (shares)				2,167
RSUs \| Inducement Grants
Restricted Stock Units
Outstanding at beginning of year (shares)				85,293
Granted (shares)				29,385
Vested (shares)				(44,909)
Expired or terminated (in shares)				(28,546)
Outstanding at end of year (shares)				41,223
Award vesting period				3 years
Performance Restricted Stock Units (RSUs)
Restricted Stock Units
Compensation expense, period for recognition				1 year 6 months
Performance Restricted Stock Units (RSUs) \| 2007 Equity Plan
Restricted Stock Units
Granted (shares)	365,591	206,250	191,250
Award vesting period				3 years
Compensation expense, period for recognition				3 years
February 2019 \| Performance Restricted Stock Units (RSUs) \| 2007 Equity Plan
Restricted Stock Units
Granted (shares)				325,091
Fair value, performance- based RSUs				$ 4.2
March 2018 \| Performance Restricted Stock Units (RSUs) \| 2007 Equity Plan
Restricted Stock Units
Granted (shares)				155,250
Fair value, performance- based RSUs				$ 2.9
February 2017 \| Performance Restricted Stock Units (RSUs) \| 2007 Equity Plan
Restricted Stock Units
Remaining number of shares available for future grants (in shares)				131,250
Fair value, performance- based RSUs				$ 2.6