Segment Information (Financial Information By Reportable Segment) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended	6 Months Ended
Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Segment Reporting Information [Line Items]
Revenue	$ 5,938	$ 7,468	$ 10,260	$ 12,082
Gross profit	4,263	4,963	7,380	8,515
Amortization of intangible assets	393	340	782	681
Intangible assets	5,763	6,206	5,763	6,206
Intersection [Member]
Segment Reporting Information [Line Items]
Revenue	3,625	3,765	5,808	6,707
Gross profit	3,242	3,171	5,347	5,905
Highway [Member]
Segment Reporting Information [Line Items]
Revenue	1,094	842	2,169	1,615
Gross profit	488	108	1,166	431
Amortization of intangible assets	121	122	244	245
Intangible assets	698	1,644	698	1,644
LPR [Member]
Segment Reporting Information [Line Items]
Revenue	1,219	2,861	2,283	3,760
Gross profit	533	1,684	867	2,176
Amortization of intangible assets	272	218	538	436
Intangible assets	$ 5,065	$ 4,562	$ 5,065	$ 4,562

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 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3602-108585

Reference 2: 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 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 30

-Section 50

-Paragraph 2

-Subparagraph (a)(2)

-URI http://asc.fasb.org/extlink&oid=26713463&loc=d3e16323-109275

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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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- Definition

Carrying amount of finite-lived intangible assets, indefinite-lived intangible assets and goodwill. Goodwill is an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized. Intangible assets are assets, not including financial assets, lacking physical substance.

+ References

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- Definition

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).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.1)

-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 1

-Article 5

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