PROPERTY, PLANT, AND EQUIPMENT - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020	Dec. 31, 2020
Property, plant and equipment
Depreciation	$ 21,500	$ 17,600	$ 42,000	$ 33,600
Property, plant and equipment, at cost	675,634		675,634		$ 589,524
Assets under construction
Property, plant and equipment
Property, plant and equipment, at cost	35,080		35,080		18,854
Laboratory equipment
Property, plant and equipment
Property, plant and equipment, at cost	168,529		168,529		142,110
Assets under construction	8,400		8,400
Leasehold and building improvements
Property, plant and equipment
Property, plant and equipment, at cost	140,314		140,314		$ 117,865
Assets under construction	19,600		19,600
Computer software
Property, plant and equipment
Assets under construction	$ 7,100		$ 7,100