Income Taxes - Narrative (Details) $ in Millions	12 Months Ended
Jun. 30, 2026 USD ($) tax_jurisdiction	Jun. 30, 2025 USD ($)	Jun. 30, 2024 USD ($)	Jun. 30, 2023 USD ($)
Operating Loss Carryforwards [Line Items]
Number of tax jurisdictions in which the entity operates (over) \| tax_jurisdiction	40
Income tax expense	14.10%	20.80%	18.00%
Increase in valuation allowance	$ (54)	$ 261	$ 3
Tax credit carryforwards	59	54
Deferred tax liability related to undistributed foreign earnings	110
Unrecognized tax benefits	212	224	104	$ 155
Interest and penalties related to uncertain tax positions	45	37	17
Income taxes paid	451	261	$ 253
HMRC
Operating Loss Carryforwards [Line Items]
Net operating losses that do not expire	$ 2,200
Other Taxing Authorities
Operating Loss Carryforwards [Line Items]
Net operating losses that do not expire		$ 2,300

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible operating loss carryforwards that are not subject to expiration dates.

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

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