LEASES- Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended	12 Months Ended
	Sep. 30, 2019	Sep. 30, 2019	Dec. 31, 2018
Leases [Abstract]
Operating lease description		The Company used the incremental borrowing rate on January 1, 2019 for operating leases that commenced prior to that date. Current lease agreements do not contain any residual value guarantees or material restrictive covenants. As of September 30, 2019, the Company did not have any finance leases and no additional operating leases that have not yet commenced.
Lessee Lease Description [Line Items]
Operating lease, right-of-use asset	$ 8,800	$ 8,800
Operating lease liabilities current	1,700	1,700
Long-term operating lease liabilities	7,100	7,100
Operating lease cost	$ 456	$ 1,316	$ 1,700
Minimum [Member]
Lessee Lease Description [Line Items]
Operating leases remaining term	1 year	1 year
Maximum [Member]
Lessee Lease Description [Line Items]
Operating leases remaining term	9 years	9 years