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Description of Business, Company History and Basis of Presentation - Additional Information (Details) - USD ($) $ in Millions | 1 Months Ended | 12 Months Ended
--- | --- | ---
May 31, 2017 | Dec. 31, 2019 | Dec. 31, 2017
Description of business and basis of presentation [Line Items] |  |  |
Percentage of ownership by the company |  | 100.00% |
Historical allocated corporate costs |  |  | $ 2.5
Spinoff |  |  |
Description of business and basis of presentation [Line Items] |  |  |
Cash transfer made to parent company | $ 650.0 |  |
TEGNA Inc | Spinoff |  |  |
Description of business and basis of presentation [Line Items] |  |  |
Date of separation | May 31, 2017 |  |

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