REVENUE RECOGNITION AND RELATED ALLOWANCES - Disaggregation of Revenue (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Revenue Recognition	$ 49,774	$ 52,887
Sales of generic pharmaceutical products [Member]
Revenue Recognition	37,495	31,599
Sales of branded pharmaceutical products [Member]
Revenue Recognition	9,157	17,543
Sales of contract manufactured products [Member]
Revenue Recognition	1,974	2,437
Royalties from licensing agreements [Member]
Revenue Recognition	290	577
Product development services [Member]
Revenue Recognition	577	320
Other [Member]
Revenue Recognition	$ 281	$ 411

Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=118956577&loc=SL49130543-203045

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=118956577&loc=SL49130545-203045

Name:	us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration