Accrued Liabilities - Schedule of Accrued Liabilities (Detail) - USD ($) $ in Millions	Sep. 30, 2020	Dec. 31, 2019
Accrued Liabilities Current [Abstract]
Accrued capital expenditures	$ 18.5	$ 34.7
Accrued interest	13.9	18.7
Other accruals	25.4	35.3
Total	$ 57.8	$ 88.7

Amount of expenses incurred but not yet paid classified as other, due within one year or the normal operating cycle, if longer.

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