Consolidated Statements of Comprehensive Income (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Statement Of Income And Comprehensive Income [Abstract]
Net Income	$ 70,119us-gaap_ProfitLoss	$ 35,133us-gaap_ProfitLoss	$ 24,321us-gaap_ProfitLoss
Other comprehensive income (loss), gross of tax:
Net gain (loss) on pension benefit obligation	(2,295)	126	(1,225)
Foreign currency translation adjustments (loss) gain	(25,044)	5,315	4,465
Unrealized loss on foreign currency derivative securities	(10)
Unrealized gain (loss) on interest rate derivative securities	81	143	(18)
Other comprehensive income (loss), gross of tax	(27,268)	5,584	3,222
Other comprehensive income, related tax effects:
Net gain on pension benefit obligation	680	18	193
Foreign currency translation adjustments	6,048	426	108
Other comprehensive income, related tax effect	6,728us-gaap_OtherComprehensiveIncomeLossTax	444us-gaap_OtherComprehensiveIncomeLossTax	301us-gaap_OtherComprehensiveIncomeLossTax
Other comprehensive income (loss), net of tax:	(20,540)	6,028	3,523
Comprehensive income:	49,579	41,161	27,844
Less: comprehensive income (loss) attributable to the non-controlling interest		(271)	7,523
Comprehensive income attributable to Gentherm Incorporated:	$ 49,579us-gaap_ComprehensiveIncomeNetOfTax	$ 41,432us-gaap_ComprehensiveIncomeNetOfTax	$ 20,321us-gaap_ComprehensiveIncomeNetOfTax

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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