Accrued Expenses - Schedule of Accrued Expenses (Detail) - USD ($) $ in Millions	Sep. 30, 2020	Dec. 31, 2019
Payables and Accruals [Abstract]
Salaries, wages and employee benefits	$ 45.9	$ 43.7
Interest	9.7	5.1
Environmental	26.1	25.2
Income tax payable	9.7	13.5
Taxes other than income taxes	9.7	9.1
Operating lease liabilities	8.9	9.3
Legal settlement	7.8	0.4
Other	36.3	31.0
Accrued expenses	$ 154.1	$ 137.3

Carrying value of the obligation (known or estimated) arising from requirements to perform activities to remediate one or more sites, payable in twelve months or in the next operating cycle if longer.

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Carrying amount as of the balance sheet date of the unpaid sum of the known and estimated amounts payable to satisfy all currently due domestic and foreign income tax obligations.

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Amounts payable for money transfers, money orders, and consumer payment service arrangements. Settlement liabilities include amounts payable to intermediaries for global payment transfers.

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Carrying value as of the balance sheet date of obligations incurred and payable for statutory income, sales, use, payroll, excise, real, property and other taxes. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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