Divestiture of Automatic License Plate Recognition Business (Details) - License Plate Recognition (TagMaster AB) [Member] $ in Thousands	3 Months Ended
Mar. 31, 2015 USD ($)
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Net revenue	$ 680
Operating loss from continuing operations	(899)
Net loss on discontinued operations, net of tax	$ (899)

Amount of operating income (loss) attributable to disposal group, including, but not limited to, discontinued operation.

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-Name Accounting Standards Codification
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-Section 50
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Amount of revenue attributable to disposal group, including, but not limited to, discontinued operation.

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Amount after tax of income (loss) from a discontinued operation attributable to the parent. Includes, but is not limited to, the income (loss) from operations during the phase-out period, gain (loss) on disposal, gain (loss) for reversal of write-down (write-down) to fair value, less cost to sell, and adjustments to a prior period gain (loss) on disposal.

+ References

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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