Selling Arrangement (Details) - Customer Contracts [Member] - USD ($)	Dec. 31, 2017	Dec. 31, 2016
Gross cost	$ 4,000,000	$ 4,000,000
Accumulated amortization	(2,683,000)	(2,283,000)
Net carrying amount	$ 1,317,000	$ 1,717,000

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

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

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- Definition

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

+ References

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- Definition

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

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