Leases - Schedule of Lease Assets and Lease Liabilities (Details) - USD ($) $ in Millions	Sep. 30, 2021	Dec. 31, 2020
Leases [Abstract]
Operating lease assets	$ 45.2	$ 26.5
Finance lease assets	$ 8.6	$ 8.1
Finance Lease, Right-of-Use Asset, Statement of Financial Position [Extensible List]	us-gaap:OtherAssets	us-gaap:OtherAssets
Total lease assets	$ 53.8	$ 34.6
Operating lease liabilities, current	$ 8.4	$ 4.4
Operating Lease, Liability, Current, Statement of Financial Position [Extensible List]	us-gaap:AccountsPayableAndAccruedLiabilitiesCurrent	us-gaap:AccountsPayableAndAccruedLiabilitiesCurrent
Finance lease liabilities, current	$ 2.1	$ 1.9
Finance Lease, Liability, Current, Statement of Financial Position [Extensible List]	us-gaap:AccountsPayableAndAccruedLiabilitiesCurrent	us-gaap:AccountsPayableAndAccruedLiabilitiesCurrent
Operating lease liabilities, noncurrent	$ 40.2	$ 25.6
Finance lease liabilities, noncurrent	$ 6.5	$ 6.2
Finance Lease, Liability, Noncurrent, Statement of Financial Position [Extensible List]	Long-term liabilities	Long-term liabilities
Total lease liabilities	$ 57.2	$ 38.1