Gentherm Global Power Technologies - Additional Information (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Business Acquisition [Line Items]
Goodwill	$ 30,398us-gaap_Goodwill	$ 25,809us-gaap_Goodwill	$ 24,729us-gaap_Goodwill
Global Thermoelectric Inc
Business Acquisition [Line Items]
Product revenues	24,235
Operating Income	776
Net assets acquired	30,759
Cash acquired on acquisition	3,061
Goodwill	6,258
Intangible Assets before Foreign Currency Adjustment	9,871
Decrease in intangible assets, net of accumulated amortization, fluctuations in foreign currency exchange rates	465
Amortization of intangibles	$ 1,962

Finite lived intangible assets gross before foreign currency adjustment..

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The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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This element represents the amount of earnings or loss of the acquiree since the acquisition date included in the consolidated income statement for the reporting period.

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This element represents the amount of revenue of the acquiree since the acquisition date included in the consolidated income statement for the reporting period.

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

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The cash inflow associated with the acquisition of business during the period (for example, cash that was held by the acquired business).

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Amount of increase (decrease) to assets, excluding financial assets and goodwill, lacking physical substance with a finite life for foreign currency translation adjustments.

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Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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