Schedule of Intangible Assets (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Finite Lived Intangible Assets [Line Items]
Gross Value	$ 121,885	$ 127,905
Accumulated Amortization	(53,756)	(44,474)
Net Value	68,129us-gaap_FiniteLivedIntangibleAssetsNet	83,431us-gaap_FiniteLivedIntangibleAssetsNet
Global Thermoelectric Inc
Finite Lived Intangible Assets [Line Items]
Gross Value	9,406
Accumulated Amortization	(1,465)
Net Value	7,941
Global Thermoelectric Inc \| Customer relationships
Finite Lived Intangible Assets [Line Items]
Gross Value	5,264
Accumulated Amortization	(334)
Net Value	4,930
Estimated useful life of intangible assets	12 years
Global Thermoelectric Inc \| Order backlog
Finite Lived Intangible Assets [Line Items]
Gross Value	777
Accumulated Amortization	(777)
Estimated useful life of intangible assets	6 months
Global Thermoelectric Inc \| Technology
Finite Lived Intangible Assets [Line Items]
Gross Value	2,675
Accumulated Amortization	(204)
Net Value	2,471
Estimated useful life of intangible assets	10 years
Global Thermoelectric Inc \| Trade Name
Finite Lived Intangible Assets [Line Items]
Gross Value	690
Accumulated Amortization	(150)
Net Value	$ 540
Estimated useful life of intangible assets	3 years 6 months

Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 30

-Section 50

-Paragraph 2

-Subparagraph (a)(1)

-URI http://asc.fasb.org/extlink&oid=26713463&loc=d3e16323-109275

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Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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