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Commitments and Contingencies - Schedule of Components of Purchase Commitments (Detail) $ in Millions | Sep. 30, 2025 USD ($)
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Long-term Purchase Commitment [Line Items] |
Payments Due by Fiscal Year 2026 | $ 216
Payments Due by Fiscal Year 2027 | 170
Payments Due by Fiscal Year 2028 | 120
Payments Due by Fiscal Year 2029 | 102
Payments Due by Fiscal Year 2030 | 100
Payments Due Thereafter | 1,037
Payments Due, Total | 1,745
Reinforcement Materials [Member] |
Long-term Purchase Commitment [Line Items] |
Payments Due by Fiscal Year 2026 | 167
Payments Due by Fiscal Year 2027 | 127
Payments Due by Fiscal Year 2028 | 95
Payments Due by Fiscal Year 2029 | 84
Payments Due by Fiscal Year 2030 | 84
Payments Due Thereafter | 870
Payments Due, Total | 1,427
Performance Chemicals [Member] |
Long-term Purchase Commitment [Line Items] |
Payments Due by Fiscal Year 2026 | 37
Payments Due by Fiscal Year 2027 | 34
Payments Due by Fiscal Year 2028 | 21
Payments Due by Fiscal Year 2029 | 16
Payments Due by Fiscal Year 2030 | 15
Payments Due Thereafter | 166
Payments Due, Total | 289
Other [Member] |
Long-term Purchase Commitment [Line Items] |
Payments Due by Fiscal Year 2026 | 12
Payments Due by Fiscal Year 2027 | 9
Payments Due by Fiscal Year 2028 | 4
Payments Due by Fiscal Year 2029 | 2
Payments Due by Fiscal Year 2030 | 1
Payments Due Thereafter | 1
Payments Due, Total | $ 29

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