Leases (Financing leases) (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Ending December 31,
2021	$ 3,774
Total future payments	3,774
Less payment related to:
Maintenance	525
Interest	33
Finance lease obligations	3,216	$ 7,379
Current portion of finance leases	3,216	4,164
Total long-term finance lease payments	$ 0	$ 3,215

Amount equal to the present value (the principal) at the beginning of the lease term of minimum lease payments during the lease term (excluding that portion of the payments representing executory costs such as insurance, maintenance, and taxes to be paid by the lessor, together with any profit thereon) net of payments or other amounts applied to the principal through the balance sheet date.

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- Definition

Amounts to be paid by lessee to lessor for maintenance, insurance, and tax expenses related to the leased asset.

+ References

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- Definition

Amount necessary to reduce net minimum lease payments to present value for capital leases.

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Present value of lessee's discounted obligation for lease payments from finance lease, classified as current.

+ References

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-Publisher FASB
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Present value of lessee's discounted obligation for lease payments from finance lease, classified as noncurrent.

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Amount of lessee's undiscounted obligation for lease payments for finance lease.

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Amount of lessee's undiscounted obligation for lease payments for finance lease, due in next fiscal year following latest fiscal year.

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