Income Taxes (Details) - USD ($) $ in Millions |
3 Months Ended | 9 Months Ended | |||
|---|---|---|---|---|---|
Jun. 30, 2026 |
Jun. 30, 2025 |
Jun. 30, 2026 |
Jun. 30, 2025 |
Sep. 30, 2025 |
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| Income Tax Examination [Line Items] | |||||
| Effective income tax rate | 18.00% | 12.30% | 18.70% | 9.90% | |
| Gross tax effected unrecognized tax benefits | $ 1,900 | ||||
| Amount of unrecognized tax benefits which may impact effective tax rate | 1,400 | ||||
| Total net accrued interest, net of tax benefit | $ 459 | ||||
| Unrecognized tax benefits, income tax penalties and interest expense | $ 74 | $ 64 | |||
| Valuation allowance adjustment | $ 36 | ||||
| IRELAND | |||||
| Income Tax Examination [Line Items] | |||||
| Ireland statutory income tax rate | 12.50% | 12.50% | 12.50% | 12.50% | |
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- Definition Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Percentage of domestic federal statutory tax rate applicable to pretax income (loss). Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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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. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of unrecognized tax benefits. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Amount of expense for interest on an underpayment of income taxes and penalties related to a tax position claimed or expected to be claimed in the tax return. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Amount of interest expense accrued for an underpayment of income taxes. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition The total amount of unrecognized tax benefits that, if recognized, would affect the effective tax rate. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Amount of increase (decrease) in the valuation allowance for a specified deferred tax asset. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Details
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