Acquisitions, Goodwill And Other Intangible Assets (Schedule of Goodwill) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017
Goodwill
Net balance, Beginning	$ 124,183	$ 89,198
Acquisitions	56,067	29,772
Other	(82)	5,213
Net balance, Ending	180,168	124,183
OEM Segment
Goodwill
Net balance, Beginning	109,641	74,663
Acquisitions	50,698	29,772
Other	(82)	5,206
Net balance, Ending	160,257	109,641
Aftermarket Segment
Goodwill
Net balance, Beginning	14,542	14,535
Acquisitions	5,369	0
Other	0	7
Net balance, Ending	$ 19,911	$ 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.

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Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

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Amount of increase (decrease), classified as other, of an asset representing the future economic benefits from other assets acquired in a business combination that are not individually identified and separately recognized.

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