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.

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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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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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- Definition

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

+ References

No definition available.

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

Amount of acquisition cost of a business combination allocated to other noncurrent assets not separately disclosed.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 141

-Paragraph 51

-Subparagraph e

-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 Emerging Issues Task Force (EITF)

-Number 98-1

-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 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 141

-Paragraph 37

-Subparagraph f

-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 property, plant and equipment to be used in ongoing operations.

+ References

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Business Acquisitions Business Acquisitions (Details textual) (USD $)	Sep. 30, 2013 Lorex Technology Inc	Dec. 31, 2012 Lorex Technology Inc	Dec. 20, 2012 Lorex Technology Inc	Sep. 30, 2013 Traficon International NV	Apr. 24, 2013 Traficon International NV	Dec. 31, 2012 Traficon International NV	Dec. 28, 2012 Traficon International NV	Apr. 16, 2013 Marine and Remote Sensing Solutions, Ltd.	Aug. 12, 2013 DigitalOptics Corporation East	Aug. 12, 2013 Thermal Vision and Measurement
Business Acquisition [Line Items]
Purchase price	$ 61,170,000		$ 61,200,000	$ 48,363,000	$ 2,100,000		$ 46,300,000	$ 3,200,000	$ 14,900,000
Net tangible assets acquired	19,121,000			5,057,000		5,100,000
Purchase price allocation to intangible assets	15,100,000			20,102,000
Purchase price allocation to goodwill	31,138,000			28,370,000
Other long-term assets		42,100,000				41,200,000
Purchase price allocation to property and equipment	1,049,000			179,000						5,000,000
Purchase price allocation to other assets	$ 3,004,000			$ 657,000						$ 9,900,000