Acquisition - Summary of Estimated Fair Value of Assets Acquired and Liabilities Assumed (Detail) (Alter Power Systems [Member], USD $) In Thousands, unless otherwise specified	Mar. 12, 2013
Alter Power Systems [Member]
Business Acquisition [Line Items]
Current assets	$ 1,053
Property and equipment	211
Intangible assets	2,806
Other assets	67
Total assets acquired	4,137
Debt (Note 11)	770
Deferred taxes and other liabilities	920
Total liabilities assumed	1,690
Total purchase price	2,447
Cash acquired	(21)
Total purchase price, net of cash acquired	$ 2,426

Business acquisition purchase price allocation deferred income taxes and other liability.

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Amount of assets acquired at the acquisition date.

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Amount of currency on hand as well as demand deposits with banks or financial institutions, acquired at the acquisition date. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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Amount of assets that are expected to be realized or consumed within one year or the normal operating cycle, if longer, acquired at the acquisition date.

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Amount of long-term debt due within one year or within the normal operating cycle, if longer, assumed at the acquisition date.

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Amount of intangible assets, excluding goodwill, acquired at the acquisition date.

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Amount of liabilities assumed at the acquisition date.

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Amount recognized as of the acquisition date for the identifiable assets acquired in excess of (less than) the aggregate liabilities assumed.

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

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Amount of other assets expected to be realized or consumed after one year or the normal operating cycle, if longer, acquired at the acquisition date.

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The amount of property, plant, and equipment recognized as of the acquisition date.

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Amount recognized for assets, including goodwill, in excess of (less than) the aggregate liabilities assumed.

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