The calculated weighted-average amortization period of a major class of finite-lived intangible assets acquired during the current period either individually or as part of a group of assets (in either an asset acquisition or business combination). A major class is composed of intangible assets that can be grouped together because they are similar, either by their nature or by their use in the operations of a company.

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Tabular disclosure of pro forma results of operations for a material business acquisition or series of individually immaterial business acquisitions that are material in the aggregate.

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

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

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The amount of acquisition cost of a business combination allocated to current liabilities of the acquired entity.

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Amount of deferred tax assets or liabilities for the differences between the values assigned and the tax bases of assets and liabilities in a business combination, net of any valuation allowance for deferred tax assets.

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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.

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The amount of acquisition cost of a business combination allocated to the noncurrent portion of the long-term debt assumed from the acquired entity.

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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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Acquisitions (Details) (USD $)	6 Months Ended		6 Months Ended
Acquisitions (Details) (USD $)	Jun. 30, 2012	Mar. 01, 2012 Israeli sales and service distributor [Member]	Jun. 30, 2012 Israeli sales and service distributor [Member] Customer Relationships [Member]	Jun. 30, 2012 Baehr [Member]	Jan. 30, 2012 Baehr [Member]	Jan. 30, 2012 Baehr [Member] Customer Relationships [Member]	Jan. 30, 2012 Baehr [Member] Unpatented Technology [Member]	Jul. 13, 2012 Blue Reference [Member]
Business Acquisition [Line Items]
Accounts receivable acquired	$ 319,000
Inventory acquired	2,887,000
Property, plant and equipment acquired	1,254,000
Other assets acquired	412,000
Goodwill acquired	10,725,000	4,000,000			7,000,000
Intangible assets acquired	7,451,000	2,000,000				1,000,000	4,000,000
Total assets acquired	23,048,000
Accrued expenses and other current liabilities acquired	2,438,000
Debt acquired	732,000				1,000,000
Deferred tax liability acquired	1,464,000
Cash paid for acquired entity	18,414,000	6,000,000			12,000,000			14,000,000
Weighted-average useful life of acquired intangible assets			10	10
Expected incremental annual sales from acquired entity	$ 10,000,000
Pro forma effect of business acquisitions	The impact of these acquisitions on the Company's net income since the acquisition date for the six months ended June 30, 2012 was not significant.