Segment Information (Details) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2017 USD ($)	Sep. 30, 2016 USD ($)	Sep. 30, 2017 USD ($)	Sep. 30, 2016 USD ($)
Segment Reporting Information [Line Items]
Number of Reportable Segments			2
Revenue	$ 3,624	$ 3,382	$ 10,183	$ 11,297
Gross profit	3,022	2,568	8,149	8,601
Amortization of intangible assets	90	0	270	0
Intangible assets	3,396	2,842	3,396	2,842
Intersection [Member]
Segment Reporting Information [Line Items]
Revenue	2,852	2,452	6,970	7,053
Gross profit	2,577	2,291	6,266	6,543
Amortization of intangible assets	90	0	270	0
Intangible assets	2,569	2,842	2,569	2,842
Highway [Member]
Segment Reporting Information [Line Items]
Revenue	772	930	3,213	4,244
Gross profit	445	277	1,883	2,058
Amortization of intangible assets	0	0	0	0
Intangible assets	$ 827	$ 0	$ 827	$ 0

The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6388964&loc=d3e16225-109274

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
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Reference 3: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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Aggregate revenue less cost of goods and services sold or operating expenses directly attributable to the revenue generation activity.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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Sum of the carrying amounts of all intangible assets, excluding goodwill, as of the balance sheet date, net of accumulated amortization and impairment charges.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

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Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

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