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Income Tax Matters - Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Millions | Dec. 31, 2024 | Dec. 31, 2023
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Deferred income tax assets: |  |
Loss and credit carryforwards | $ 17.3 | $ 39.6
Defined benefit plans | 3.1 | 3.6
Other assets | 35.8 | 36.8
Lease assets | 7.2 | 8.7
Inventories | 39.8 | 29.5
Excess interest carryforward | 10.2 | 14.0
Research & development capitalization | 19.1 | 16.9
Valuation allowances | (5.5) | (2.7)
Total deferred income tax assets | 127.0 | 146.4
Deferred income tax liabilities: |  |
Property, plant and equipment | (133.3) | (142.6)
Lease liabilities | (7.2) | (8.7)
Undistributed foreign earnings | (3.4) | (3.0)
Total deferred income tax liabilities | (143.9) | (154.3)
Net deferred income tax liabilities | $ (16.9) | $ (7.9)

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