Leases - ROU Assets and Liabilities (Details) $ in Millions	Jun. 30, 2020 USD ($)
Operating lease assets:
Other assets	$ 52.0
Operating lease liabilities:
Other accrued liabilities	11.5
Other liabilities	50.3
Total operating lease liabilities	$ 61.8
Operating Lease, Liability, Current, Statement of Financial Position [Extensible List]	us-gaap:AccruedLiabilitiesCurrent
Operating Lease, Liability, Noncurrent, Statement of Financial Position [Extensible List]	us-gaap:AccruedLiabilitiesNoncurrent