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Supplemental Cash Flow Information - Schedule Of Noncash Investing and Financing Activities (Detail) - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020
Supplemental Cash Flow Elements [Abstract]
Right-of-use assets obtained in exchange for new finance lease liabilities	$ 158.8	$ 1.1
Accrued liabilities for purchases of property, plant and equipment	29.5	22.0
Right-of-use assets obtained in exchange for new operating lease liabilities	13.2	18.0
Remeasurement of operating lease right-of-use assets	$ (6.3)	$ 1.1

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- Definition

Remeasurement of operating leases right of use assets.

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- Definition

Future cash outflow to pay for purchases of fixed assets that have occurred.

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Amount of increase in right-of-use asset obtained in exchange for finance lease liability.

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