Components of Lease Expense (Details) $ in Millions	12 Months Ended
	Dec. 31, 2019 USD ($)
Finance lease cost:
Amortization of finance lease assets	$ 1.5
Interest on lease liabilities	1.2
Total finance lease cost	2.7
Operating lease cost	70.2
Short-term lease cost	19.2
Variable lease cost	13.7
Total lease cost	$ 105.8