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Segment Reporting (Schedule Of Automotive And Other Segment Reporting) (Details) - USD ($) | 3 Months Ended
--- | ---
Mar. 31, 2017 | Mar. 31, 2016
Segment Reporting Information [Line Items] |  |
Revenue | $ 453,535,250 | $ 405,567,786
Income from operations | 134,427,120 | 120,848,990
Automotive Products |  |
Segment Reporting Information [Line Items] |  |
Revenue | 445,652,575 | 393,968,947
Income from operations | 132,504,957 | 115,980,617
Other |  |
Segment Reporting Information [Line Items] |  |
Revenue | 7,882,675 | 11,598,839
Income from operations | $ 1,922,163 | $ 4,868,373

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- Definition Aggregate revenue during the period from the sale of goods in the normal course of business, after deducting returns, allowances and discounts. + 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(a)) -URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688 + Details
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