Stock-based compensation - Narrative (Details) - USD ($) $ in Millions		3 Months Ended
Jul. 01, 2026	Sep. 30, 2026
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Unrecognized compensation expense, options		$ 22
Granted (in shares)		0
Service-based RSUs
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Unrecognized compensation expense, RSUs		$ 594
Weighted-average remaining vesting period (in years)		2 years 2 months 1 day
Granted (in shares)		20,372,928
Performance-based RSUs
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Unrecognized compensation expense, RSUs		$ 47
Weighted-average remaining vesting period (in years)		1 year 10 months 2 days
Granted (in shares)		448,547
Performance-based RSUs \| Tranche one
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Granted (in shares)		448,547
Vesting period (in years)		3 years
Stock options
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Weighted-average remaining vesting period (in years)		3 years 10 months 24 days
2025 Omnibus Plan
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Number of shares authorized (in shares)	8,000,000.0
Number of ordinary shares authorized (in shares)		25,500,000

Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Amount of cost to be recognized for nonvested award under share-based payment arrangement. Excludes share and unit options.

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