Share-based payments - $75 Exercise Price Options (Details)		12 Months Ended
Sep. 14, 2021 shares $ / shares	Jun. 30, 2024 shares tranche $ / shares
Share-based payments [Abstract]
Number of tranches \| tranche		3
$75 Exercise Price Options
Share-based payments [Abstract]
Exercise price (in dollars per share) \| $ / shares		$ 75
Contractual exercise period		12 years
Number of tranches \| tranche		4
Number of share outstanding (in shares) \| shares		24,195,092
$75 Exercise Price Options \| Entities Controlled by Daniel Roberts
Share-based payments [Abstract]
Granted during the year (in shares) \| shares	2,400,000
Exercise price (in dollars per share) \| $ / shares		$ 75
$75 Exercise Price Options \| Entities Controlled by William Roberts
Share-based payments [Abstract]
Granted during the year (in shares) \| shares	2,400,000
Exercise price (in dollars per share) \| $ / shares		$ 75
$75 Exercise Price Options \| Tranche One
Share-based payments [Abstract]
Number of trading days		20 days
Volume weighted average market price (in dollars per share) \| $ / shares	$ 370
Number of share options expected to vest (in shares) \| shares	600,000
$75 Exercise Price Options \| Tranche Two
Share-based payments [Abstract]
Number of trading days		20 days
Volume weighted average market price (in dollars per share) \| $ / shares	$ 650
Number of share options expected to vest (in shares) \| shares	600,000
$75 Exercise Price Options \| Tranche Three
Share-based payments [Abstract]
Number of trading days		20 days
Volume weighted average market price (in dollars per share) \| $ / shares	$ 925
Number of share options expected to vest (in shares) \| shares	600,000
$75 Exercise Price Options \| Tranche Four
Share-based payments [Abstract]
Number of trading days		20 days
Volume weighted average market price (in dollars per share) \| $ / shares	$ 1,850
Number of share options expected to vest (in shares) \| shares	600,000

The number of share options outstanding in a share-based payment arrangement.

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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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The number of share options granted in a share-based payment arrangement.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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The weighted average exercise price of share options granted in a share-based payment arrangement. [Refer: Weighted average [member]]

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The contractual life of share options granted, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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The number of Long-term Target share options expected to vest in a share-based payment arrangement.

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Number of consecutive trading days, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Number of employment service tranches.

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Share-based payment [Abstract]

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The volume weighted average market price of options in a share-based payment arrangement.

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