The total cost of the acquired entity including the cash paid to shareholders of acquired entities, fair value of debt and equity securities issued to shareholders of acquired entities, the fair value of the liabilities assumed, and direct costs of the acquisition.

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 141

-Paragraph 51

-Subparagraph d

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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- Definition

The amount of acquisition cost of a business combination allocated to assets acquired.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 141

-Paragraph 37

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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- Definition

Amount of goodwill arising from a business combination, which is the excess of the cost of the acquired entity over the amounts assigned to assets acquired and liabilities assumed.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 141

-Paragraph 52

-Subparagraph c

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 141

-Paragraph 53

-Subparagraph d

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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Amount of acquisition cost of a business combination allocated to assets, excluding financial assets and goodwill, lacking physical substance.

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Amount of acquisition cost of a business combination allocated to other assets not separately disclosed in the balance sheet.

+ References

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Business Acquisitions Business Acquisitions (Details textual) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2013 Lorex Technology Inc	Dec. 31, 2012 Lorex Technology Inc	Dec. 20, 2012 Lorex Technology Inc	Mar. 31, 2013 Traficon International NV	Dec. 31, 2012 Traficon International NV	Dec. 28, 2012 Traficon International NV
Business Acquisition [Line Items]
Cash paid for acquisition	$ 61,170		$ 61,170	$ 46,288		$ 46,288
Purchase price allocation to intangible assets	15,100			19,838
Purchase price allocation to goodwill	26,949			21,393
Net tangible assets		19,100			5,100
Other long-term assets		$ 42,000			$ 41,200