Industry Segments (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2014 Segment	Mar. 31, 2013
Segment Reporting Information [Line Items]
Number of reportable operating segments	2
Net sales	$ 232,752	$ 230,708
Intersegment revenue	0	0
Operating profit	20,405	16,030
Engine Management [Member]
Segment Reporting Information [Line Items]
Net sales	179,294	175,509
Intersegment revenue	5,953	5,453
Operating profit	24,372	20,784
Temperature Control [Member]
Segment Reporting Information [Line Items]
Net sales	51,485	52,728
Intersegment revenue	2,234	1,509
Operating profit	613	(454)
All Other [Member]
Segment Reporting Information [Line Items]
Net sales	1,973	2,471
Intersegment revenue	(8,187)	(6,962)
Operating profit	$ (4,580)	$ (4,300)

Amount of revenue from transactions with other operating segments of the same entity.

No definition available.

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- Definition

Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

+ References

No definition available.

+ Details

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- Definition

The net result for the period of deducting operating expenses from operating revenues.

+ References

No definition available.

+ Details

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- Definition

Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.1)

-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 1

-Article 5

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