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Goodwill and Other Intangible Assets (Schedule of Intangible Assets) (Details) - USD ($) | 12 Months Ended
--- | ---
Dec. 31, 2019 | Dec. 31, 2018
Schedule of Finite-Lived and Indefinite-Lived Intangible Assets [Line Items] |  |
Intangible assets, net | $ 250,375,000 | $ 269,675,000
HomeLink® |  |
Schedule of Finite-Lived and Indefinite-Lived Intangible Assets [Line Items] |  |
Finite-lived intangible assets, accumulated amortization | (120,625,000) | (101,325,000)
Intangible assets, gross | 371,000,000 | 371,000,000
Intangible assets, net | 250,375,000 | 269,675,000
HomeLink® | Homelink Technology |  |
Schedule of Finite-Lived and Indefinite-Lived Intangible Assets [Line Items] |  |
Finite-lived intangible assets, gross | 180,000,000 | 180,000,000
Finite-lived intangible assets, accumulated amortization | (93,750,000) | (78,750,000)
Finite-lived intangible assets, net | $ 86,250,000 | $ 101,250,000
Finite-lived intangible asset, useful life | 12 years | 12 years
HomeLink® | Existing Customer Platforms |  |
Schedule of Finite-Lived and Indefinite-Lived Intangible Assets [Line Items] |  |
Finite-lived intangible assets, gross | $ 43,000,000 | $ 43,000,000
Finite-lived intangible assets, accumulated amortization | (26,875,000) | (22,575,000)
Finite-lived intangible assets, net | $ 16,125,000 | $ 20,425,000
Finite-lived intangible asset, useful life | 10 years | 10 years
HomeLink® | HomeLink Trade Names and Trademarks |  |
Schedule of Finite-Lived and Indefinite-Lived Intangible Assets [Line Items] |  |
Indefinite-lived intangible assets | $ 52,000,000 | $ 52,000,000
HomeLink® | Exclusive Licensing Agreement |  |
Schedule of Finite-Lived and Indefinite-Lived Intangible Assets [Line Items] |  |
Indefinite-lived intangible assets | $ 96,000,000 | $ 96,000,000

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- Definition Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275 + Details
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