Cash and Cash Equivalents - Schedule of Cash and Cash Equivalents (Detail) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Cash and cash equivalents [abstract]
Cash at bank and on hand	$ 886.8	$ 515.0
Total cash and cash equivalents	$ 886.8	$ 515.0	$ 219.7	$ 393.8

The amount of cash on hand and demand deposits, along with short-term, highly liquid investments that are readily convertible to known amounts of cash and that are subject to an insignificant risk of changes in value. [Refer: Cash; Cash equivalents]

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