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Segment Reporting (Schedule of Major Product Line Revenues) (Details) - USD ($) | 3 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2018 | Sep. 30, 2018 | Jun. 30, 2018 | Mar. 31, 2018 | Dec. 31, 2017 | Sep. 30, 2017 | Jun. 30, 2017 | Mar. 31, 2017 | Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016
Revenue from External Customer [Line Items] |  |  |  |  |  |  |  |  |  |  |
Revenues | $ 453,409,000 | $ 460,253,000 | $ 454,981,000 | $ 465,420,000 | $ 459,570,000 | $ 438,628,000 | $ 443,139,000 | $ 453,535,000 | $ 1,834,063,697 | $ 1,794,872,578 | $ 1,678,924,756
Automotive Products |  |  |  |  |  |  |  |  |  |  |
Revenue from External Customer [Line Items] |  |  |  |  |  |  |  |  |  |  |
Revenues |  |  |  |  |  |  |  |  | 1,791,198,296 | 1,758,127,468 | 1,639,692,243
Automotive Products | Automotive Mirrors |  |  |  |  |  |  |  |  |  |  |
Revenue from External Customer [Line Items] |  |  |  |  |  |  |  |  |  |  |
Revenues |  |  |  |  |  |  |  |  | 1,598,589,777 | 1,573,222,820 | 1,456,963,758
Automotive Products | HomeLink Modules |  |  |  |  |  |  |  |  |  |  |
Revenue from External Customer [Line Items] |  |  |  |  |  |  |  |  |  |  |
Revenues |  |  |  |  |  |  |  |  | 192,608,519 | 184,904,648 | 182,728,485
Other |  |  |  |  |  |  |  |  |  |  |
Revenue from External Customer [Line Items] |  |  |  |  |  |  |  |  |  |  |
Revenues |  |  |  |  |  |  |  |  | 42,865,401 | 36,745,110 |
Other | Other Products Revenue |  |  |  |  |  |  |  |  |  |  |
Revenue from External Customer [Line Items] |  |  |  |  |  |  |  |  |  |  |
Revenues |  |  |  |  |  |  |  |  | $ 42,865,401 | $ 36,745,110 | $ 39,232,513

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