Commitments and Contingencies - Schedule of Future Lease Payments Under Operating Leases (Detail) $ in Millions	Sep. 30, 2019 USD ($)
Commitments And Contingencies Disclosure [Abstract]
2019 (excluding the nine months ended September 30, 2019)	$ 21.6
2020	69.0
2021	52.4
2022	34.1
2023	23.8
2024 and thereafter	32.9
Total lease payments	233.8
Less: Amount representing interest	32.9
Present value of lease obligation	$ 200.9
Weighted average remaining lease term	4 years 1 month 6 days
Weighted average discount rate	6.60%

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Amount of lessee's undiscounted obligation for lease payments for operating lease.

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Amount of lessee's undiscounted obligation for lease payments for operating lease, due after fifth fiscal year following latest fiscal year.

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Amount of lessee's undiscounted obligation for lease payments for operating lease, due in second fiscal year following latest fiscal year.

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Amount of lessee's undiscounted obligation for lease payments for operating lease having an initial or remaining lease term in excess of one year due in remainder of fiscal year following latest fiscal year.

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Amount of lessee's undiscounted obligation for lease payments in excess of discounted obligation for lease payments for operating lease.

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Present value of lessee's discounted obligation for lease payments from operating lease.

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Weighted average discount rate for operating lease calculated at point in time.

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Weighted average remaining lease term for operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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