Segment Information (Details) $ in Thousands	3 Months Ended
Mar. 31, 2020 USD ($)	Mar. 31, 2019 USD ($)
Segment Reporting Information [Line Items]
Number of Reportable Segments	2
Revenue	$ 3,159	$ 3,372
Gross profit	2,536	2,595
Amortization of intangible assets	174	150
Intangible assets	3,722	3,586
Intersection [Member]
Segment Reporting Information [Line Items]
Revenue	2,250	2,072
Gross profit	2,069	1,792
Amortization of intangible assets	92	92
Intangible assets	1,651	2,018
Highway [Member]
Segment Reporting Information [Line Items]
Revenue	909	1,300
Gross profit	467	803
Amortization of intangible assets	82	58
Intangible assets	$ 2,071	$ 1,568

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.

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