LEASES - LEASE COST (Details) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2021 USD ($) location	Jun. 30, 2020 USD ($) location	Jun. 30, 2021 USD ($) location	Jun. 30, 2020 USD ($) location
Leases [Abstract]
Operating lease cost	$ 3,557	$ 3,607	$ 6,894	$ 7,098
Finance lease cost:
Amortization of right-of-use assets	0	5	3	7
Interest on lease liabilities	0	1	1	2
Short-term lease cost	164	292	211	1,882
Variable lease cost	95	(135)	65	(44)
Sublease income	(91)	(89)	(183)	(178)
Total lease cost	3,725	3,681	6,991	8,767
Office rent expense	$ 500	$ 300	$ 800	$ 500
Number of office spaces, portion subleased \| location	1	1	1	1

Operating Lease, Expense, Office Rent

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Operating Lease, Number Of Office Spaces Subleased

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Amount of interest expense on finance lease liability.

+ References

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Amount of amortization expense attributable to right-of-use asset from finance lease.

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Amount of lease cost recognized by lessee for lease contract.

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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.

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Amount of short-term lease cost, excluding expense for lease with term of one month or less.

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Amount of sublease income excluding finance and operating lease expense.

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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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