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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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