Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 235
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-Topic 740
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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.

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Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations, attributable to increase (decrease) in the income tax rates.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
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Amount of unrecognized tax benefits.

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-Topic 740
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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.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
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Amount of interest expense accrued for an underpayment of income taxes.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 15
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The total amount of unrecognized tax benefits that, if recognized, would affect the effective tax rate.

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Income Taxes - Narrative (Details) - USD ($) $ in Millions		3 Months Ended		6 Months Ended
Income Taxes - Narrative (Details) - USD ($) $ in Millions	Jan. 01, 2024	Mar. 31, 2024	Mar. 31, 2023	Mar. 31, 2024	Mar. 31, 2023	Sep. 30, 2023
Income Tax Examination [Line Items]
Effective income tax rate		35.20%	22.00%	305.00%	16.00%
Gross tax effected unrecognized tax benefits						$ 2,200
Amount of unrecognized tax benefits which may impact effective tax rate						1,600
Total net accrued interest, net of tax benefit						$ 335
Unrecognized tax benefits, income tax penalties and interest expense				$ 60	$ 56
IRELAND
Income Tax Examination [Line Items]
Ireland statutory income tax rate		12.50%	12.50%	12.50%	12.50%
SWITZERLAND
Income Tax Examination [Line Items]
Ireland statutory income tax rate	15.00%
Noncash discrete net tax benefit				$ 80