ACQUISITIONS - Schedule of Pro Forma Information (Details) - Flexion - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Business Acquisition [Line Items]
Total revenues	$ 630,942	$ 515,199
Net loss	$ (67,264)	$ (19,711)
Pro forma basic net loss per share (in usd per share)	$ (1.52)	$ (0.46)
Pro forma diluted net loss per share (in usd per share)	$ (1.52)	$ (0.46)