Acquisitions, Goodwill And Other Intangible Assets (Schedule Of Goodwill By Reportable Segment) (Details) $ in Thousands	6 Months Ended
Jun. 30, 2017 USD ($)
Segment Reporting Information
Net balance – December 31, 2016	$ 89,198
Acquisitions – 2017	29,277
Other	3,800
Net balance – June 30, 2017	122,275
OEM Segment
Segment Reporting Information
Net balance – December 31, 2016	74,663
Acquisitions – 2017	29,277
Other	3,793
Net balance – June 30, 2017	107,733
Aftermarket Segment
Segment Reporting Information
Net balance – December 31, 2016	14,535
Acquisitions – 2017	0
Other	7
Net balance – June 30, 2017	$ 14,542

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6388280&loc=d3e13770-109266

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=77989000&loc=SL49117168-202975

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