LEASES - Reported under ASC 842 and ASC 840 (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Jan. 01, 2019	Dec. 31, 2018
Future minimum lease payments for non-cancellable operating leases
Remaining period in 2019	$ 1,028
2020	1,360
2021	876
2022	574
2023	585
Thereafter	345
Total operating lease payment	4,768
Less: discount to present value	395
Total operating lease liabilities	4,373
Less: current operating lease liabilities	1,625	$ 2,103
Noncurrent operating lease liabilities	$ 2,748	$ 3,444
Prior to the adoption of ASC 842, future obligations for non-cancellable operating leases
2019			$ 3,792
2020			2,350
2021			1,899
2022			968
2023			999
Thereafter			599
Total operating lease payments			$ 10,607

Amount of lessee's undiscounted obligation for lease payments for operating lease.

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Amount of lessee's undiscounted obligation for lease payments for operating lease having an initial or remaining lease term in excess of one year due in remainder of fiscal year following latest fiscal year.

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