Leases - Supplemental Balance Sheet Information Related to Leases (Detail) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Operating Leased Assets [Line Items]
Right of use lease asset	$ 34.8	$ 32.0
Financing lease assets noncurrent	$ 8.6	$ 8.8
Finance Lease, Right-of-Use Asset, Statement of Financial Position [Extensible List]	us-gaap:PropertyPlantAndEquipmentNet	us-gaap:PropertyPlantAndEquipmentNet
Total lease assets	$ 50.5	$ 47.5
Finance lease liability current	$ 2.9	$ 4.0
Finance Lease, Liability, Current, Statement of Financial Position [Extensible List]	us-gaap:LongTermDebtCurrent	us-gaap:LongTermDebtCurrent
Operating lease liability current	$ 8.4	$ 8.8
Finance lease liability Noncurrent	$ 8.5	$ 8.4
Finance Lease, Liability, Noncurrent, Statement of Financial Position [Extensible List]	us-gaap:LongTermDebtNoncurrent	us-gaap:LongTermDebtNoncurrent
Operating lease liability noncurrent	$ 32.8	$ 30.1
Total lease liabilities	52.6	51.3
Trade And Other Receivables Net
Operating Leased Assets [Line Items]
Operating lease assets current	5.2	5.5
Prepaid Expenses and Other Current Assets
Operating Leased Assets [Line Items]
Operating lease assets current	$ 1.9	$ 1.2