LICENSE AGREEMENTS AND COMMITMENTS - Lease maturities (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Future minimum commitments under all non-cancelable operating leases
Remainder of 2019	$ 378
2020	756
2021	760
2022	649
2023	539
Thereafter	77
Total lease payments	3,159
Less: Imputed interest	(677)
Total operating lease liabilities	$ 2,482
Future minimum commitments under all non-cancelable operating leases, 2018
2019		$ 510
2020		616
2021		616
2022		616
2023		462
Thereafter		64
Total lease payments		$ 2,884

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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