Leases - Schedule of Maturities of Lease Liabilities (Detail) - USD ($) $ in Millions	Jun. 30, 2020	Dec. 31, 2019	Jun. 30, 2019
Finance Lease Liabilities, Payments, Due [Abstract]
2020	$ 0.8
2021	1.5
2022	1.1
2023	0.6
2024	0.1
Total lease payments	4.1
Less: imputed interest	(0.4)
Total future lease obligation	3.7	$ 4.2	$ 4.2
Operating Lease Liabilities, Payments Due [Abstract]
2020	6.1
2021	10.7
2022	8.5
2023	7.0
2024	4.3
Thereafter	9.0
Total lease payments	45.6
Less: imputed interest	(6.8)
Total future lease obligation	$ 38.8	$ 41.3	$ 34.7