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Revenue (Details) - USD ($) | 3 Months Ended | 9 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 | Sep. 30, 2018 | Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016
Disaggregation of Revenue [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 Segment |  |  |  |  |  |  |  |  |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Revenues |  |  |  |  |  |  |  |  |  | 1,791,198,296 | 1,758,127,468 |
Other |  |  |  |  |  |  |  |  |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Revenues |  |  |  |  |  |  |  |  |  | 42,865,401 | 36,745,110 |
Automotive Products |  |  |  |  |  |  |  |  |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Revenues |  |  |  |  |  |  |  |  |  | 1,791,198,296 | 1,758,127,468 |
Automotive Mirrors & Electronics | Automotive Segment |  |  |  |  |  |  |  |  |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Revenues |  |  |  |  |  |  |  |  |  | 1,598,589,777 | 1,573,222,820 |
Automotive Mirrors & Electronics | Automotive Segment | Minimum |  |  |  |  |  |  |  |  |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Payment terms |  |  |  |  |  |  |  |  | 15 days |  |  |
Automotive Mirrors & Electronics | Automotive Segment | Maximum |  |  |  |  |  |  |  |  |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Payment terms |  |  |  |  |  |  |  |  | 90 days |  |  |
HomeLink Modules | Automotive Segment |  |  |  |  |  |  |  |  |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Revenues |  |  |  |  |  |  |  |  |  | 192,608,519 | 184,904,648 |
Other Products (U.S.) | Other |  |  |  |  |  |  |  |  |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Revenues |  |  |  |  |  |  |  |  |  | 42,865,401 | 36,745,110 | $ 39,232,513
Fire Protection Products | Other |  |  |  |  |  |  |  |  |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Revenues |  |  |  |  |  |  |  |  |  | 22,109,784 | 18,790,474 |
Fire Protection Products | Other | Minimum |  |  |  |  |  |  |  |  |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Payment terms |  |  |  |  |  |  |  |  | 30 days |  |  |
Fire Protection Products | Other | Maximum |  |  |  |  |  |  |  |  |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Payment terms |  |  |  |  |  |  |  |  | 75 days |  |  |
Windows Products | Other |  |  |  |  |  |  |  |  |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Revenues |  |  |  |  |  |  |  |  |  | 20,755,617 | 17,954,636 |
Dimmable Aircraft Windows | Other | Minimum |  |  |  |  |  |  |  |  |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Payment terms |  |  |  |  |  |  |  |  | 30 days |  |  |
Dimmable Aircraft Windows | Other | Maximum |  |  |  |  |  |  |  |  |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Payment terms |  |  |  |  |  |  |  |  | 45 days |  |  |
U.S. | Automotive Products |  |  |  |  |  |  |  |  |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Revenues |  |  |  |  |  |  |  |  |  | 583,672,971 | 567,492,812 |
U.S. | Other Products (U.S.) |  |  |  |  |  |  |  |  |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Revenues |  |  |  |  |  |  |  |  |  | 42,865,401 | 36,745,110 |
Germany | Automotive Products |  |  |  |  |  |  |  |  |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Revenues |  |  |  |  |  |  |  |  |  | 333,002,878 | 351,123,204 |
Japan | Automotive Products |  |  |  |  |  |  |  |  |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Revenues |  |  |  |  |  |  |  |  |  | 209,311,790 | 185,261,067 |
Other | Automotive Products |  |  |  |  |  |  |  |  |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Revenues |  |  |  |  |  |  |  |  |  | $ 665,210,657 | $ 654,250,385 |

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