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Percentage of stock interest on subsidiaries pledge to secure obligation.

+ References

No definition available.

+ Details

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Namespace Prefix:	thrm_
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Period Type:	instant

- Definition

The amount of debt discount that was originally recognized at the issuance of the instrument that has yet to be amortized.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 45

-Paragraph 1A

-URI http://asc.fasb.org/extlink&oid=6451184&loc=d3e28541-108399

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 55

-Paragraph 8

-URI http://asc.fasb.org/extlink&oid=34725769&loc=d3e28878-108400

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount of current borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any amounts currently outstanding under the facility.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.19(b),22(b))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 19, 22

-Article 5

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Name:	us-gaap_LineOfCreditFacilityCurrentBorrowingCapacity
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Date the credit facility terminates, in CCYY-MM-DD format.

+ References

+ Details

Name:	us-gaap_LineOfCreditFacilityExpirationDate1
Namespace Prefix:	us-gaap_
Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

- Definition

The effective interest rate during the reporting period.

+ References

+ Details

Name:	us-gaap_LineOfCreditFacilityInterestRateDuringPeriod
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Carrying amount of collateralized debt obligations with maturities initially due after one year or beyond the operating cycle, if longer, excluding the current portion. Obligations include, but not limited to, mortgage loans, chattel loans, and other borrowings secured by assets.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

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Balance Type:	credit
Period Type:	instant

Debt - Additional Information (Detail) In Thousands, unless otherwise specified	0 Months Ended				0 Months Ended		9 Months Ended		0 Months Ended	9 Months Ended
	Aug. 07, 2014 USD ($)	Aug. 07, 2014 Revolving Credit Facility USD ($)	Aug. 07, 2014 US Term Note USD ($)	Aug. 07, 2014 Europe Term Loan EUR (€)	Aug. 07, 2014 Federal Funds Purchased Minimum	Aug. 07, 2014 Federal Funds Purchased Maximum	Sep. 30, 2014 US Bank of America credit facility Maximum	Sep. 30, 2014 Eurocurrency Rate Loans	Aug. 07, 2014 Eurocurrency Rate Loans Minimum	Sep. 30, 2014 Eurocurrency Rate Loans Minimum	Sep. 30, 2014 Eurocurrency Rate Loans Maximum	Sep. 30, 2014 Base Rate Loans	Sep. 30, 2014 Base Rate Loans Minimum	Sep. 30, 2014 Base Rate Loans Maximum
Debt Disclosure [Line Items]
Secured term loan facility borrowing capacity			$ 50,000	€ 20,000
Secured long-term debt		100,000
Line of credit facility		50,000
Maximum percentage of stock of non US subsidaries pledge to secure obligation	66.00%
Debt retirement expense	$ 730
Credit facility maturity date	Aug. 07, 2019
Interest rate					0.07%	0.50%	3.25%	1.75%	1.00%	1.50%	2.00%	0.75%	0.50%	1.00%