LEASES -  Maturity of remaining lease liabilities (Details) $ in Thousands  | 
 Mar. 31, 2019  
USD ($) 
 | 
|---|---|
| Summary of the maturity of remaining lease liabilities: | |
| 2019 | $ 316 | 
| 2020 | 451 | 
| 2021 | 420 | 
| 2022 | 417 | 
| 2023 | 398 | 
| 2024 and thereafter | 1,085 | 
| Total | 3,087 | 
| Less: Interest | $ (326) | 
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- Definition Amount of lessee's undiscounted obligation for lease payments for operating lease. Reference 1: http://www.xbrl.org/2003/role/disclosureRef 
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- Definition Amount of lessee's undiscounted obligation for lease payments for operating lease, due after fifth fiscal year following latest fiscal year. Reference 1: http://www.xbrl.org/2003/role/disclosureRef 
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- Definition Amount of lessee's undiscounted obligation for lease payments for operating lease, due in next fiscal year following latest fiscal year. Reference 1: http://www.xbrl.org/2003/role/disclosureRef 
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- Definition Amount of lessee's undiscounted obligation for lease payments for operating lease, due in fifth fiscal year following latest fiscal year. Reference 1: http://www.xbrl.org/2003/role/disclosureRef 
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- Definition Amount of lessee's undiscounted obligation for lease payments for operating lease, due in fourth fiscal year following latest fiscal year. Reference 1: http://www.xbrl.org/2003/role/disclosureRef 
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- Definition Amount of lessee's undiscounted obligation for lease payments for operating lease, due in third fiscal year following latest fiscal year. Reference 1: http://www.xbrl.org/2003/role/disclosureRef 
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- Definition Amount of lessee's undiscounted obligation for lease payments for operating lease, due in second fiscal year following latest fiscal year. Reference 1: http://www.xbrl.org/2003/role/disclosureRef 
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- Definition Amount of lessee's undiscounted obligation for lease payments in excess of discounted obligation for lease payments for operating lease. Reference 1: http://www.xbrl.org/2003/role/disclosureRef 
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- References No definition available. 
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