Benefit Obligation, Amounts Recognized Company's Financial Statements and Principal Assumptions (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Change in projected benefit obligation:
Benefit obligation at beginning of year	$ 1,848	$ 1,633
Service cost	335us-gaap_DefinedBenefitPlanServiceCost	355us-gaap_DefinedBenefitPlanServiceCost
Interest cost	78us-gaap_DefinedBenefitPlanInterestCost	53us-gaap_DefinedBenefitPlanInterestCost
Actuarial (gains)/losses	213	(193)
Net periodic benefit cost	626	215
Benefit obligation at end of year	2,474	1,848
Gentherm GmbH
Change in projected benefit obligation:
Benefit obligation at beginning of year	6,019	5,392
Service cost	304
Interest cost	181	180
Paid pension distributions	(278)	(291)
Actuarial (gains)/losses	1,385	43
Past service cost	1,271	445
Exchange rate impact	(762)	250
Benefit obligation at end of year	$ 8,120	$ 6,019

Defined benefit plan amortization of past service cost credit.

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- Definition

Amount of gain (loss) related to change in benefit obligation resulting from changes in actuarial assumptions, for example, but not limited to, interest, mortality, employee turnover, salary, and temporary deviation from the substantive plan.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

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- Definition

1) For defined benefit pension plans, the benefit obligation is the projected benefit obligation, which is the actuarial present value as of a date of all benefits attributed by the pension benefit formula to employee service rendered prior to that date. 2) For other postretirement defined benefit plans, the benefit obligation is the accumulated postretirement benefit obligation, which is the actuarial present value of benefits attributed to employee service rendered to a particular date.

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- Definition

The amount of payments made for which participants are entitled under a pension plan, including pension benefits, death benefits, and benefits due on termination of employment. Also includes payments made under a postretirement benefit plan, including prescription drug benefits, health care benefits, life insurance benefits, and legal, educational and advisory services. This item represents a periodic decrease to the plan obligations and a decrease to plan assets.

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-Glossary Postretirement Benefits

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- Definition

Amount of gain (loss) from foreign currency exchange rate changes for benefit obligation for plans of a foreign operation whose functional currency is not the reporting currency.

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- Definition

The increase in a defined benefit pension plan's projected benefit obligation or a defined benefit postretirement plan's accumulated postretirement benefit obligation due to the passage of time.

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The total amount of net periodic benefit cost for defined benefit plans for the period. Periodic benefit costs include the following components: service cost, interest cost, expected return on plan assets, gain (loss), prior service cost or credit, transition asset or obligation, and gain (loss) due to settlements or curtailments.

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- Definition

The actuarial present value of benefits attributed by the pension benefit formula to services rendered by employees during the period. The portion of the expected postretirement benefit obligation attributed to employee service during the period. The service cost component is a portion of the benefit obligation and is unaffected by the funded status of the plan.

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