Leases - Lease Cost and Other Information (Details) $ in Millions	3 Months Ended	9 Months Ended
	Sep. 30, 2019 USD ($)	Sep. 30, 2019 USD ($)
Finance Leases [Abstract]
Amortization of ROU assets	$ 2.4	$ 6.5
Interest on lease liabilities	0.5	1.5
Operating leases	7.4	23.7
Short-term lease cost	2.0	3.9
Variable lease cost	1.6	4.7
Total lease cost	$ 13.9	40.3
Cash paid for amounts included in the measurement of lease liabilities:
Operating cash flows from finance leases		3.9
Operating cash flows from operating leases		26.1
Financing cash flows from finance leases		6.5
Right-Of-Use Asset Obtained In Exchange For Lease Liability [Abstract]
ROU assets obtained in exchange for new finance lease liabilities		19.6
ROU assets obtained in exchange for new operating lease liabilities		$ 14.5
Finance leases
Remaining lease term (in years)	6 years 4 months 24 days	6 years 4 months 24 days
Discount rate	5.00%	5.00%
Operating leases
Remaining lease term (in years)	4 years 10 months 24 days	4 years 10 months 24 days
Discount rate	5.40%	5.40%