Schedule II-Valuation and Qualifying Accounts (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Allowance For Credit Losses
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Year	$ 10.9	$ 12.8	$ 11.9
"Additions" Charged to Costs and Expenses	7.5	5.5	8.1
"Other" Additions (Deductions)	0.0	0.0	0.0
"Less" Deductions	6.1	7.4	7.2
Balance at End of Year	12.3	10.9	12.8
Insurance Reserves
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Year	41.1	37.6	39.0
"Additions" Charged to Costs and Expenses	72.1	69.7	66.9
"Other" Additions (Deductions)	0.0	0.0	0.0
"Less" Deductions	72.2	66.2	68.3
Balance at End of Year	$ 41.0	$ 41.1	$ 37.6