Goodwill and Other Intangible Assets (Details)	12 Months Ended															12 Months Ended						12 Months Ended						1 Months Ended		12 Months Ended	1 Months Ended	12 Months Ended			12 Months Ended				12 Months Ended
	Dec. 31, 2013 USD ($)		Dec. 31, 2012 USD ($)		Dec. 31, 2011 USD ($)	Dec. 31, 2013 Customer Relationships [Member] USD ($)	Dec. 31, 2012 Customer Relationships [Member] USD ($)	Dec. 31, 2013 Trademarks and Trade Names [Member] USD ($)	Dec. 31, 2012 Trademarks and Trade Names [Member] USD ($)	Dec. 31, 2013 Non-compete Agreements [Member] USD ($)	Dec. 31, 2012 Non-compete Agreements [Member] USD ($)	Dec. 31, 2013 Patents and Supply Contracts [Member] USD ($)	Dec. 31, 2012 Patents and Supply Contracts [Member] USD ($)	Dec. 31, 2013 Leaseholds [Member] USD ($)	Dec. 31, 2012 Leaseholds [Member] USD ($)	Dec. 31, 2013 Computer Software [Member] USD ($)	Dec. 31, 2012 Computer Software [Member] USD ($)	Dec. 31, 2011 Computer Software [Member] USD ($)	Dec. 31, 2013 Computer Software [Member] Minimum [Member]	Dec. 31, 2013 Computer Software [Member] Maximum [Member]	Dec. 31, 2013 Dana Acquisition [Member] Trademarks and Trade Names [Member] USD ($)	Dec. 31, 2013 CompressorWorks, Inc. [Member] USD ($)	Dec. 31, 2012 CompressorWorks, Inc. [Member] USD ($)	Dec. 31, 2012 CompressorWorks, Inc. [Member] Customer Relationships [Member] USD ($)	Dec. 31, 2012 CompressorWorks, Inc. [Member] Trademarks and Trade Names [Member] USD ($)	Dec. 31, 2012 CompressorWorks, Inc. [Member] Non-compete Agreements [Member] USD ($)	Dec. 31, 2012 CompressorWorks, Inc. [Member] Leaseholds [Member] USD ($)	Feb. 28, 2013 SMP Europe [Member] USD ($)	Feb. 28, 2013 SMP Europe [Member] GBP (£)	Dec. 31, 2013 SMP Europe [Member] USD ($)	Feb. 28, 2013 SMP Europe [Member] Customer Relationships [Member] USD ($)	Dec. 31, 2013 SMP Europe [Member] Customer Relationships [Member] USD ($)	Dec. 31, 2013 Engine Management [Member] USD ($)	Dec. 31, 2011 Engine Management [Member] USD ($)	Dec. 31, 2012 Engine Management [Member] CompressorWorks, Inc. [Member] USD ($)	Dec. 31, 2013 Engine Management [Member] SMP Europe [Member] USD ($)	Dec. 31, 2013 Temperature Control [Member] USD ($)	Dec. 31, 2011 Temperature Control [Member] USD ($)	Dec. 31, 2012 Temperature Control [Member] CompressorWorks, Inc. [Member] USD ($)	Dec. 31, 2013 Temperature Control [Member] SMP Europe [Member] USD ($)
Goodwill [Line Items]
Percentage in excess of its carrying amount (in hundredths)																																	120.00%				60.00%
Goodwill by operating segment [Abstract]
Goodwill gross, Beginning balance	$ 74,315,000		$ 64,612,000																														$ 64,612,000	$ 64,612,000			$ 9,703,000	$ 0
Goodwill accumulated impairment loss, Beginning balance	(38,488,000)		(38,488,000)																														(38,488,000)	(38,488,000)			0	0
Goodwill net, Beginning balance	35,827,000		26,124,000																														26,124,000	26,124,000			9,703,000	0
Goodwill acquired during period																							9,703,000					2,000,000		2,027,000					0	2,027,000			9,703,000	0
Goodwill foreign currency exchange rate change	151,000																																151,000				0
Goodwill gross, Ending balance	76,493,000		74,315,000		64,612,000																												66,790,000	64,612,000			9,703,000	0
Goodwill accumulated impairment loss, Ending balance	(38,488,000)		(38,488,000)		(38,488,000)																												(38,488,000)	(38,488,000)			0	0
Goodwill net, Ending balance	38,005,000		35,827,000		26,124,000																	9,703,000											28,302,000	26,124,000			9,703,000	0
Purchase price paid in cash																						38,594,000	38,600
Purchase price excluding working capital adjustment																							37,400,000
Working capital adjustment																							1,200,000
Purchase price of business																												6,500,000	4,200,000
Goodwill acquired in business acquisition																							9,703,000					2,000,000		2,027,000					0	2,027,000			9,703,000	0
Acquired Indefinite-lived Intangible Assets [Line Items]
Total acquired intangible assets	52,772,000		48,693,000			44,179,000	40,100,000	6,800,000	6,800,000	910,000	910,000	723,000	723,000	160,000	160,000
Less accumulated amortization	(19,202,000)	[1]	(14,210,000)	[1]
Net acquired intangible assets	33,570,000		34,483,000
Intangible assets acquired [Abstract]
Amount of acquired indefinite-lived intangible assets																					5,200,000
Amount of acquired intangible assets																							8,900,000	8,000,000	500,000	200,000	200,000
Intangible assets acquired in business acquisition																															3,800,000	3,800,000
Estimated useful life of intangible assets																			3 years	10 years				7 years	3 years	3 years	2 years 3 months 18 days				10 years	10 years
Amortization of acquired intangible assets [Abstract]
Amortization expense	5,000,000		4,700,000		2,100,000
Estimated amortization expense in year 2014	4,500,000
Estimated amortization expense in year 2015	4,300,000
Estimated amortization expense in year 2016	4,200,000
Estimated amortization expense in years 2017 through 2028	15,400,000
Other intangible assets	16,800,000		17,300,000
Accumulated computer software amortization	15,500,000		15,200,000
Amortization of computer software																$ 600,000	$ 500,000	$ 700,000

[1] Applies to all intangible assets, except for the Dana acquisition related trademarks and trade names totaling $5.2 million, which have indefinite useful lives and, as such, are not being amortized.