Leases - Components of Net Lease Cost (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Finance leases
Amortization of right-of-use assets	$ 449	$ 520	$ 1,427	$ 1,665
Interest on lease liabilities	62	75	194	236
Operating lease cost	1,306	1,303	3,885	3,892
Short-term lease cost	104	85	324	288
Variable lease cost	304	349	983	1,039
Sublease income	(84)	(81)	(246)	(250)
Net lease cost	$ 2,141	$ 2,251	$ 6,567	$ 6,870

Finance lease.

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- Definition

Amount of interest expense on finance lease liability.

+ References

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- Definition

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

+ References

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- Definition

Amount of lease cost recognized by lessee for lease contract.

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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

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

+ 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.

+ References

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