Annual report pursuant to Section 13 and 15(d)

Cover
- Document and Entity Information
Financial Statements
Notes to Financial Statements
Accounting Policies
- Summary of Significant Accounting Policies (Policies)
Notes Tables
Notes Details

Permit and Other Intangible Assets - Schedule of Finite-Lived Intangible Assets (Details)

v3.8.0.1

Permit and Other Intangible Assets - Schedule of Finite-Lived Intangible Assets (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Finite-Lived Intangible Asset, Useful Life	10 years	10 years
Gross Carrying Amount	$ 4,982	$ 4,897
Accumulated Amortization	(3,433)	(3,059)
Finite-Lived Intangible Assets, Net	1,549	1,838
Patent [Member]
Gross Carrying Amount	657	577
Accumulated Amortization	(306)	(274)
Finite-Lived Intangible Assets, Net	$ 351	303
Patent [Member] \| Minimum [Member]
Finite-Lived Intangible Asset, Useful Life	1 year
Patent [Member] \| Maximum [Member]
Finite-Lived Intangible Asset, Useful Life	17 years
Software [Member]
Finite-Lived Intangible Asset, Useful Life	3 years
Gross Carrying Amount	$ 410	405
Accumulated Amortization	(398)	(383)
Finite-Lived Intangible Assets, Net	$ 12	22
Customer Relationships [Member]
Finite-Lived Intangible Asset, Useful Life	12 years
Gross Carrying Amount	$ 3,370	3,370
Accumulated Amortization	(2,246)	(1,974)
Finite-Lived Intangible Assets, Net	$ 1,124	1,396
Permit [Member]
Finite-Lived Intangible Asset, Useful Life	10 years
Gross Carrying Amount	$ 545	545
Accumulated Amortization	(483)	(428)
Finite-Lived Intangible Assets, Net	$ 62	$ 117

- Definition

Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

Name:	us-gaap_FiniteLivedIntangibleAssetUsefulLife
Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount before amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

+ Details

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Namespace Prefix:	us-gaap_
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Period Type:	instant

- Details

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- Details

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- Details

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- Details

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- Details

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