Business Acquisitions Business Acquisitions (Details 2) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2013
Lorex Technology Inc
Business Acquisition [Line Items]
Identifiable intangible assets	$ 15,100
Traficon International NV
Business Acquisition [Line Items]
Identifiable intangible assets	19,838
Lorex Trade Name \| Lorex Technology Inc
Business Acquisition [Line Items]
Indefinite-Lived Intangible Assets	6,800
Patented/Proprietary Technology \| Traficon International NV
Business Acquisition [Line Items]
Finite-Lived Intangible Assets	5,951
Weighted average estimated useful life	10 years
Backlog \| Traficon International NV
Business Acquisition [Line Items]
Finite-Lived Intangible Assets	1,587
Weighted average estimated useful life	1 year 6 months
Customer Relationships \| Lorex Technology Inc
Business Acquisition [Line Items]
Finite-Lived Intangible Assets	8,300
Weighted average estimated useful life	7 years
Customer Relationships \| Traficon International NV
Business Acquisition [Line Items]
Finite-Lived Intangible Assets	$ 12,300
Weighted average estimated useful life	10 years

Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 30

-Section 50

-Paragraph 1

-Subparagraph (a)(3)

-URI http://asc.fasb.org/extlink&oid=7658586&loc=d3e16265-109275

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- Details

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- Definition

The amount of acquisition cost of a business combination allocated to an identifiable intangible asset that will be amortized.

+ 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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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 Statement of Financial Accounting Standard (FAS)

-Number 141

-Paragraph 52

-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 an identifiable intangible asset that will not be amortized. Does not include goodwill.

+ 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 Statement of Financial Accounting Standard (FAS)

-Number 141

-Paragraph 52

-Subparagraph b

-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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