REVENUE FROM CONTRACTS WITH CUSTOMERS - Reconciliation of Contract Balances (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
	Jun. 30, 2020	Jun. 30, 2020	Sep. 30, 2019
Contract with Customer, Liability [Abstract]
Contract liabilities (current)	$ 9,410	$ 9,410	$ 5,008
Contract liabilities (noncurrent)	1,019	1,019	$ 1,130
Change in Contract with Customer, Liability [Abstract]
Revenue recognized in contract liability	$ 400	$ 3,427