Financial Instruments and Risk Management - Fair Value of Hedging Contracts (Details) - USD ($) $ in Millions	Sep. 30, 2026	Dec. 31, 2025
Assets:
Total assets	$ 0.5	$ 0.5
Liabilities:
Total liabilities	1.1	1.4
Level 1
Assets:
Total assets	0.0	0.0
Liabilities:
Total liabilities	0.0	0.0
Level 2
Assets:
Total assets	0.5	0.5
Liabilities:
Total liabilities	1.1	1.4
Level 3
Assets:
Total assets	0.0	0.0
Liabilities:
Total liabilities	0.0	0.0
Natural gas contracts
Liabilities:
Total liabilities	0.6	0.5
Natural gas contracts \| Level 1
Liabilities:
Total liabilities	0.0	0.0
Natural gas contracts \| Level 2
Liabilities:
Total liabilities	0.6	0.5
Natural gas contracts \| Level 3
Liabilities:
Total liabilities	0.0	0.0
Currency exchange contracts
Assets:
Total assets	0.5	0.5
Liabilities:
Total liabilities	0.5	0.5
Currency exchange contracts \| Level 1
Assets:
Total assets	0.0	0.0
Liabilities:
Total liabilities	0.0	0.0
Currency exchange contracts \| Level 2
Assets:
Total assets	0.5	0.5
Liabilities:
Total liabilities	0.5	0.5
Currency exchange contracts \| Level 3
Assets:
Total assets	0.0	0.0
Liabilities:
Total liabilities	$ 0.0	0.0
Interest rate swap contracts
Liabilities:
Total liabilities		0.4
Interest rate swap contracts \| Level 1
Liabilities:
Total liabilities		0.0
Interest rate swap contracts \| Level 2
Liabilities:
Total liabilities		0.4
Interest rate swap contracts \| Level 3
Liabilities:
Total liabilities		$ 0.0