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Self-Insurance (Details) - USD ($) $ in Millions | Dec. 31, 2019 | Dec. 31, 2018
--- | --- | ---
Insurance [Line Items] |  |
Self-insurance reserves - current portion | $ 708.5 | $ 679.9
Self-insurance reserves - long-term portion | 262.4 | 275.0
Self-insurance reserves [Member] |  |
Insurance [Line Items] |  |
Self-insurance reserves - current portion | 32.3 | 29.9
Self-insurance reserves - long-term portion | 48.0 | 47.4
Total self-insurance liabilities | $ 80.3 | $ 77.3

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