INTANGIBLE ASSETS - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018	Jun. 30, 2016
Finite-Lived Intangible Assets [Line Items]
Net book value of amortizable intangible assets	$ 159,753		$ 186,691
Impairment of IPR&D intangibles	25,500	$ 0
IPR&D asset	233,375		255,643
Acquired Product Rights L-UDCA
Finite-Lived Intangible Assets [Line Items]
Impairment of IPR&D intangibles	$ 25,500
IPR&D asset			$ 25,500	$ 25,500