Amount after tax of increase (decrease) to equity or (increase) decrease to net assets, resulting from the cumulative effect adjustment of a new accounting principle applied in the period of adoption.

No definition available.

+ Details

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- Definition

Amount of lessee's right to use underlying asset under operating lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 45
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=77888419&loc=SL77918627-209977

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- Definition

The portion of the gain that will be recorded as income or a reduction in rent expense in future periods less amounts recognized in the current period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 40
-Section 35
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=108788860&loc=d3e50609-112754

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Accounting Pronouncements Recently Issued Narrative - Impact of implementation of new accounting standards (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017	Dec. 31, 2016
Sale Leaseback Transaction, Deferred Gain, Net	$ 1,000
Accounting Standards Update 2016-01 [Member]
Cumulative Effect of New Accounting Principle in Period of Adoption		$ 0
Accounting Standards Update 2016-09 [Member]
Cumulative Effect of New Accounting Principle in Period of Adoption			$ 67
Retained Earnings [Member] \| Accounting Standards Update 2016-01 [Member]
Cumulative Effect of New Accounting Principle in Period of Adoption		$ (157)
Retained Earnings [Member] \| Accounting Standards Update 2016-09 [Member]
Cumulative Effect of New Accounting Principle in Period of Adoption			(117)
Common Stock [Member] \| Accounting Standards Update 2016-09 [Member]
Cumulative Effect of New Accounting Principle in Period of Adoption			$ 184
Minimum [Member]
Operating Lease, Right-of-Use Asset	40,000
Maximum [Member]
Operating Lease, Right-of-Use Asset	$ 50,000