POSTRETIREMENT BENEFITS - Weighted-Average Asset Allocations (Details)	Sep. 30, 2025	Sep. 30, 2024
Defined Benefit Plan Disclosure [Line Items]
Plan asset allocations (as a percent)	100.00%	100.00%
Debt securities
Defined Benefit Plan Disclosure [Line Items]
Plan asset allocations (as a percent)	97.00%	96.00%
Cash and cash equivalents
Defined Benefit Plan Disclosure [Line Items]
Plan asset allocations (as a percent)	3.00%	4.00%

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.

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+ Details