The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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GOODWILL AND INTANGIBLE ASSETS - Components (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
INTANGIBLE ASSETS
Gross Carrying Amount	$ 366,568		$ 366,568		$ 355,170
Accumulated Amortization	(196,427)		(196,427)		$ (166,659)
Weighted Average Amortization Period					9 years 4 months 24 days
Amortization of intangible assets	10,100	$ 10,100	29,800	$ 30,200
Intangible asset impairment charge	0	$ 0	0	$ 0
Acquired ANDA intangible assets
INTANGIBLE ASSETS
Gross Carrying Amount	106,415		106,415		$ 106,415
Accumulated Amortization	(51,684)		$ (51,684)		(42,367)
Weighted Average Amortization Period			8 years 9 months 18 days
NDAs and product rights
INTANGIBLE ASSETS
Gross Carrying Amount	242,372		$ 242,372		230,974
Accumulated Amortization	(132,146)		$ (132,146)		(112,483)
Weighted Average Amortization Period			9 years 10 months 24 days
Marketing and distribution rights
INTANGIBLE ASSETS
Gross Carrying Amount	17,157		$ 17,157		17,157
Accumulated Amortization	(12,107)		$ (12,107)		(11,386)
Weighted Average Amortization Period			5 years 8 months 12 days
Non-compete agreement
INTANGIBLE ASSETS
Gross Carrying Amount	624		$ 624		624
Accumulated Amortization	$ (490)		$ (490)		$ (423)
Weighted Average Amortization Period			7 years