Leases - Schedule of Lease Assets and Liabilities Included on Condensed Consolidated Balance Sheet (Detail) $ in Millions	Sep. 30, 2019 USD ($)
Operating Leases:
Operating lease right-of-use assets	$ 39.5
Current maturities of operating lease right-of-use assets	9.6
Operating lease right-of-use liabilities, less current maturities	30.5
Total operating lease liabilities	40.1
Finance Leases:
Gross property, plant and equipment	10.0
Accumulated depreciation	(4.9)
Property, plant and equipment, net	$ 5.1
Finance Lease, Right-of-Use Asset, Statement of Financial Position [Extensible List]	us-gaap:PropertyPlantAndEquipmentNet
Current maturities of long-term lease liabilities	$ 1.4
Long-term lease liabilities, less current maturities	2.9
Total finance lease liabilities	$ 4.3