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v3.21.1

Supplemental Cash Flow Information - Schedule Of Noncash Investing and Financing Activities (Detail) - USD ($) $ in Millions | 3 Months Ended
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Mar. 31, 2021 | Mar. 31, 2020
Supplemental Cash Flow Elements [Abstract] |  |
Right-of-use assets obtained in exchange for new finance lease liabilities | $ 115.1 |
Accrued liabilities for purchases of property, plant and equipment | 28.7 | $ 21.4
Right-of-use assets obtained in exchange for new operating lease liabilities | 6.0 | 12.7
Accrued proceeds from company-owned life insurance benefits |  | $ 0.8
Remeasurement of operating lease right-of-use assets | $ (6.2) |

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