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Employee Benefit Plans - Defined Benefit Pension Plans Weighted-Average Asset Allocations (Detail) - Foreign Plans [Member] | Sep. 30, 2023 | Sep. 30, 2022
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Defined Benefit Plan Disclosure [Line Items] |  |  |
Equity securities |  | 19.00% | 20.00%
Debt securities |  | 31.00% | 68.00%
Real estate |  | 10.00% | 7.00%
Cash and other securities | [1] | 40.00% | 5.00%
Total |  | 100.00% | 100.00%
[1] | The asset allocation is temporarily changed as a result of the insurance contracts Cabot Carbon Limited Pension Plan and Carbon Plastics Pension Plan purchased with plan assets in anticipation of the settlement discussed above.

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- Definition Percentage of defined benefit plan debt securities. + References No definition available. + Details
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- Definition Percentage of defined benefit plan equity securities. + References No definition available. + Details
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- Definition Percentage of defined benefit plan real estate. + References No definition available. + Details
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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- Definition Percentage of actual investment allocation to total plan assets. Includes, but is not limited to, percentage on weighted-average basis if more than one plan. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (d)(i) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480506/715-20-50-1 + Details
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- Details
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