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v3.23.3

Other (Expense) Income, Net (Details) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2023 | Sep. 30, 2022 | Sep. 30, 2023 | Sep. 30, 2022
Other Income and Expenses [Abstract] |  |  |  |
Interest income | $ 0.6 | $ 0.4 | $ 1.2 | $ 0.6
Net periodic postretirement benefit cost | (2.2) | (1.4) | (6.1) | (4.3)
Unrealized (loss) gain on equity securities | (0.1) | (0.3) | 0.2 | (1.4)
(Loss) gain on disposition of property, plant and equipment | (0.2) | 8.4 | 14.0 | 6.3
Post-acquisition funding received from Alcoa Corporation |  | 6.0 |  | 6.0
All other, net | (0.3) | (0.4) | (0.4) | 0.2
Other (expense) income, net | $ (2.2) | $ 12.7 | $ 8.9 | $ 7.4

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