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Supplemental Cash Flow Information - Schedule Of Noncash Investing and Financing Activities (Detail) - USD ($) $ in Millions | 9 Months Ended
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Sep. 30, 2020 | Sep. 30, 2019
Supplemental Cash Flow Elements [Abstract] |  |
Accrued liabilities for purchases of property, plant and equipment | $ 30.5 | $ 28.8
Right-of-use assets obtained in exchange for new operating lease liabilities | 29.3 | 36.4
Right-of-use assets obtained in exchange for new finance lease liabilities | 15.0 | 0.2
Remeasurement of operating lease right-of-use assets | $ 1.9 |
Acquisition of assets through swap |  | $ 1.1

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