Revenue - Summary of Revenues Disaggregated by Product Line (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Disaggregation Of Revenue [Line Items]
Revenue	$ 7,802.4	$ 8,478.0	$ 7,730.3
Packaging
Disaggregation Of Revenue [Line Items]
Revenue	7,135.6	7,780.7	7,052.6
Paper
Disaggregation Of Revenue [Line Items]
Revenue	595.4	622.1	599.7
Corporate and Other
Disaggregation Of Revenue [Line Items]
Revenue	$ 71.4	$ 75.2	$ 78.0