Supplemental Cash Flow Information - Schedule of Noncash Investing and Financing Activities (Detail) - USD ($) $ in Millions	9 Months Ended
Sep. 30, 2021	Sep. 30, 2020
Supplemental Cash Flow Elements [Abstract]
Right-of-use assets obtained in exchange for new finance lease liabilities	$ 177.8	$ 15.0
Right-of-use assets obtained in exchange for new operating lease liabilities	17.3	29.3
Accrued liabilities for purchases of property, plant and equipment	28.6	30.5
Remeasurement of operating lease right-of-use assets	$ (12.4)	$ 1.9

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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- Definition

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

+ References

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-Publisher FASB
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- Definition

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

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- References

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