Leases (Finance leases) (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Ending October 1,
2021	$ 5,323
Total future payments	5,323
Less payments related to:
Maintenance	978
Interest	73
Present value of future minimum finance lease payments	4,272	$ 7,379
Less: Current portion	(4,272)	(4,164)
Total long-term finance lease payments	$ 0	$ 3,215

Less payments related to:

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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

Reference 1: http://fasb.org/us-gaap/role/ref/otherTransitionRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 30
-Section 50
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+ Details

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- Definition

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

+ References

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- Definition

Present value of lessee's discounted obligation for lease payments from finance lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
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-Publisher FASB
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+ Details

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
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-Paragraph 1
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- Definition

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

+ References

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- Definition

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

+ References

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- Definition

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

+ References

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- References

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