Leases - Components of lease expenses (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020
Finance lease cost:
Amortization of assets	$ 1,013	$ 1,038
Interest on lease liabilities	469	489
Operating lease expense:
Operating lease cost	2,232	2,263
Variable lease cost	270	264
Sublease income	(49)	(48)
Total lease costs	$ 3,935	$ 4,006

Finance Lease Cost [Abstract]

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- Definition

n/a

+ References

No definition available.

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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

+ Details

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- Definition

Amount of lease cost recognized by lessee for lease contract.

+ References

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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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- 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

+ Details

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