LEASES - Lease Costs & Additional Lease Information (Details) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2019 USD ($)	Jun. 30, 2019 USD ($)
Leases [Abstract]
Operating lease cost	$ 833	$ 1,667
Variable lease cost	0	0
Sublease income	(633)	(1,258)
Total lease cost	$ 200	$ 409
Weighted-average remaining lease term - operating leases (in years)	2 years 1 month 6 days	2 years 1 month 6 days
Weighted-average discount rate - operating leases (as a percent)	4.13%	4.13%

Amount of lease cost recognized by lessee for lease contract.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=77888426&loc=SL77918686-209980

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- References

No definition available.

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- Definition

Amount of single lease cost, calculated by allocation of remaining cost of lease over remaining lease term. Includes, but is not limited to, single lease cost, after impairment of right-of-use asset, calculated by amortization of remaining right-of-use asset and accretion of lease liability.

+ References

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-Publisher FASB
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- Definition

Weighted average discount rate for operating lease calculated at point in time.

+ References

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- Definition

Weighted average remaining lease term for operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

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- Definition

Amount of sublease income excluding finance and operating lease expense.

+ References

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- Definition

Amount of variable lease cost, excluded from lease liability, recognized when obligation for payment is incurred for finance and operating leases.

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