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Goodwill and Other Intangible Assets (Narrative) (Details) - USD ($) | 3 Months Ended | 9 Months Ended |  |
--- | --- | --- | --- | ---
Sep. 30, 2021 | Mar. 31, 2021 | Dec. 31, 2020 | Sep. 30, 2020 | Jun. 30, 2020 | Sep. 30, 2021 | Sep. 30, 2020 | Mar. 03, 2021 | Dec. 31, 2013
Finite-Lived Intangible Assets [Line Items] |  |  |  |  |  |  |  |  |  |
Goodwill | $ 314,805,654 |  | $ 311,922,787 | [1] |  |  | $ 314,805,654 |  |  |
Acquisitions |  |  |  |  |  |  | 2,848,364 |  |  |
Amortization of intangible assets | 5,500,000 |  |  |  | $ 5,600,000 |  | 16,700,000 | $ 16,800,000 |  |
Amortization expense, remainder of fiscal year | 22,000,000 |  |  |  |  |  | 22,000,000 |  |  |
Amortization expense, year one | 22,000,000 |  |  |  |  |  | 22,000,000 |  |  |
Amortization expense, year two | 20,000,000 |  |  |  |  |  | 20,000,000 |  |  |
Amortization expense, year three | 16,000,000 |  |  |  |  |  | 16,000,000 |  |  |
Amortization expense, year four | 12,000,000 |  |  |  |  |  | $ 12,000,000 |  |  |
HomeLink® |  |  |  |  |  |  |  |  |  |
Finite-Lived Intangible Assets [Line Items] |  |  |  |  |  |  |  |  |  |
Goodwill |  |  |  |  |  |  |  |  |  | $ 307,400,000
Vaporsens Inc |  |  |  |  |  |  |  |  |  |
Finite-Lived Intangible Assets [Line Items] |  |  |  |  |  |  |  |  |  |
Acquisitions |  |  |  |  |  | $ 3,700,000 |  |  |  |
Argil, Inc. |  |  |  |  |  |  |  |  |  |
Finite-Lived Intangible Assets [Line Items] |  |  |  |  |  |  |  |  |  |
Acquisitions |  |  | $ 900,000 |  |  |  |  |  |  |
Goodwill, period increase (decrease) | (100,000) |  |  |  |  |  |  |  |  |
Air-CraftGlass |  |  |  |  |  |  |  |  |  |
Finite-Lived Intangible Assets [Line Items] |  |  |  |  |  |  |  |  |  |
Goodwill, period increase (decrease) | $ 200,000 |  |  |  |  |  |  |  |  |
Guardian Optical Technologies |  |  |  |  |  |  |  |  |  |
Finite-Lived Intangible Assets [Line Items] |  |  |  |  |  |  |  |  |  |
Goodwill |  |  |  |  |  |  |  |  | $ 2,848,364 |
Acquisitions |  | $ 2,800,000 |  |  |  |  |  |  |  |
[1] | The condensed consolidated balance sheet at December 31, 2020 has been derived from the audited consolidated financial statements at that date but does not include all of the information and footnotes required by accounting principles generally accepted in the United States for complete financial statements.

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