Business Acquisitions Business Acquisitions (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2013 Lorex Technology Inc	Dec. 20, 2012 Lorex Technology Inc	Mar. 31, 2013 Traficon International NV	Dec. 28, 2012 Traficon International NV
Business Acquisition [Line Items]
Cash acquired	$ 1,170		$ 181
Accounts receivable, net	10,183		6,435
Inventories	13,967		2,853
Property and equipment	1,049		179
Other assets	3,004		657
Liabilities	(10,252)		(5,248)
Net tangible assets	19,121		5,057
Identifiable intangible assets	15,100		19,838
Goodwill	26,949		21,393
Purchase price	$ 61,170	$ 61,170	$ 46,288	$ 46,288

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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The amount of cash and cash equivalents acquired in a business combination.

+ References

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- Definition

The amount of acquisition cost of a business combination allocated to inventory, including finished goods, work-in-process, and raw materials.

+ References

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The amount of acquisition cost of a business combination allocated to receivables.

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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

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

+ References

No definition available.

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The amount of acquisition cost of a business combination allocated to liabilities assumed.

+ References

Reference 1: 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.

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

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No definition available.

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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

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-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)

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-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.

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