Summary of Significant Accounting Policies - Revenue Recognition, Share-Based Compensation and Foreign Currencies (Details) $ in Millions	12 Months Ended
Dec. 31, 2022 USD ($) item	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)
Revenue Recognition
Number of performance obligations from sales of metal products \| item	1
Shipping and handling costs included in operating expenses	$ 509.7	$ 424.6	$ 357.4
Share-Based Compensation
Stock-based compensation expense	65.3	70.8	42.2
Foreign Currencies
Net gain (loss) resulting from foreign currency transactions	$ (6.2)	$ (4.0)	$ (2.3)
Toll processing
Revenue Recognition
Number Of Days To Perform Services	1 day

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Represents the number of performance obligation from sale of metal products.

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Cost incurred during the reporting period in transporting goods and services to customers. Includes freight-out cost.

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Amount before tax of foreign currency transaction realized and unrealized gain (loss) recognized in the income statement.

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Amount of noncash expense for share-based payment arrangement.

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