Acquisition (Details) (Aarding Thermal Acoustics [Member], USD $) In Thousands, unless otherwise specified	Mar. 31, 2013
Aarding Thermal Acoustics [Member]
Fair values of the assets acquired and liabilities assumed at the date of closing
Current assets	$ 15,062
Property and equipment	959
Goodwill	16,572
Intangible - finite life, net	3,271
Intangible - indefinite life	1,963
Total assets acquired	37,827
Current liabilities assumed	(9,585)
Net assets acquired	$ 28,242

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

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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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