LEASES - Components of lease expense (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019
Lease cost
Operating lease cost	$ 2,541	$ 2,935
Amortization of right-of-use assets	53	15
Interest on lease liabilities	5	3
Short-term lease cost	41	30
Variable lease cost	304	319
Sublease income	(245)	(243)
Total lease cost	2,699	3,059
Supplemental cash flow information related to leases was as follows
Operating cash flows from finance leases	53	13
Operating cash flows from operating leases	3,284	3,412
Financing cash flows from finance leases	$ 6	$ 10

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Amount of interest expense on finance lease liability.

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Amount of interest paid on finance lease liability.

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Amount of cash outflow for principal payment on finance lease.

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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 cash outflow from operating lease, excluding payments to bring another asset to condition and location necessary for its intended use.

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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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