Leases - Summary of Location and Amount of Lease Assets and Lease Liabilities (Detail) - USD ($) $ in Millions		Mar. 31, 2020	Dec. 31, 2019
Assets
Operating lease assets		$ 121.5	$ 128.2
Finance lease assets		$ 54.1	$ 54.2
Finance lease, Right-of-use asset, Statement of financial position [Extensible List]	[1]	us-gaap:PropertyPlantAndEquipmentNet	us-gaap:PropertyPlantAndEquipmentNet
Total lease assets		$ 175.6	$ 182.4
Liabilities
Operating lease liabilities, current		21.2	20.9
Finance lease liabilities, current		$ 11.9	$ 12.4
Finance lease, Liability, Current, Statement of financial position [Extensible List]		us-gaap:OtherAccruedLiabilitiesCurrent	us-gaap:OtherAccruedLiabilitiesCurrent
Operating lease liabilities, noncurrent		$ 106.2	$ 112.8
Finance lease liabilities, noncurrent		$ 17.6	$ 18.7
Finance Lease, Liability, Noncurrent, Statement of Financial Position [Extensible List]		us-gaap:OtherLiabilitiesNoncurrent	us-gaap:OtherLiabilitiesNoncurrent
Total lease liabilities		$ 156.9	$ 164.8

[1] Finance lease assets were recorded net of accumulated amortization of $19.3 million and $19.0 million as of March 31, 2020 and December 31, 2019, respectively.