Debt (Non-Recourse Debt Associated With NGHC) (Details) - USD ($) $ in Billions	Jun. 30, 2025	Sep. 30, 2024
Variable Interest Entity, Primary Beneficiary \| Nonrecourse \| NEOM Green Hydrogen Company
Debt Instrument [Line Items]
Total principal borrowings	$ 4.6	$ 3.3

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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