ACQUISITION-RELATED (GAINS) CHARGES, RESTRUCTURING CHARGES AND OTHER - Acquisition Related Charges (Gains) and Other (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Restructuring Cost and Reserve [Line Items]
Severance-related expenses	$ 0	$ 950	$ 0	$ 4,065
Total acquisition-related charges	709	3,222	1,198	8,630
Changes in contingent consideration			6,640	22,351
Restructuring charges	936	0	936	0
Total acquisition-related (gains) charges, restructuring charges and other	(16,613)	(18,058)	(4,506)	(13,721)
Flexion
Restructuring Cost and Reserve [Line Items]
Changes in contingent consideration	(18,258)	(12,523)	(6,640)	(13,317)
Myoscience Acquisition
Restructuring Cost and Reserve [Line Items]
Changes in contingent consideration	0	(8,757)	0	(9,034)
Acquisition-related fees
Restructuring Cost and Reserve [Line Items]
Acquisition-related costs	709	2,168	1,198	4,013
Other acquisition expenses
Restructuring Cost and Reserve [Line Items]
Acquisition-related costs	$ 0	$ 104	$ 0	$ 552

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Business Combination, Acquisition And Integration Related Costs

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This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities.

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Amount of increase (decrease) in the value of a contingent consideration liability, including, but not limited to, differences arising upon settlement.

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Costs incurred to effect a business combination which have been expensed during the period. Such costs could include business integration costs, systems integration and conversion costs, and severance and other employee-related costs.

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Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation.

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