Leases (Finance leases) (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Ending July 1,
2020	$ 6,168
2021	6,672
2022	180
Total future payments	13,020
Less payments related to:
Maintenance	3,196
Interest	424
Present value of future minimum finance lease payments	9,400	$ 11,380
Less: Current portion	(4,081)
Total long-term finance lease payments	$ 5,319

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/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 30
-Section 50
-Paragraph 1
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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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- 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
-Section 45
-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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- Definition

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

+ References

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- Definition

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

+ References

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- References

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