SEGMENT AND GEOGRAPHIC INFORMATION - Summary of Long-Lived Assets by Geographic Region (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-lived assets	$ 28,936	$ 20,998
United States
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-lived assets	16,754	13,146
China
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-lived assets	4,635	5,504
Mexico
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-lived assets	3,510	0
Other
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-lived assets	$ 4,037	$ 2,348