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Revenues - Narrative (Details) - USD ($) $ in Millions | Dec. 31, 2019 | Dec. 31, 2018 | Jan. 01, 2018
--- | --- | --- | ---
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |  |
Charge back reserve | $ 49.7 | $ 46.4 |
Adjustment due to Topic 606 | Maintenance and Repair Services |  |  |
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |  |
Cumulative effect adjustments to retained earnings |  |  | $ 4.8
Adjustment due to Topic 606 | Vehicle Financing, Sale of Service and Insurance Contracts |  |  |
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |  |
Cumulative effect adjustments to retained earnings |  |  | $ 6.6

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