Share-based payments - Long-Term Incentive Plan Restricted Stock Units (Details)	12 Months Ended
Jun. 30, 2024 shares tranche	Jun. 30, 2023 shares tranche $ / shares
Share-based payments [Abstract]
Number of tranches \| tranche	3
2022 Long-Term Incentive Plan Restricted Stock Units ("2022 LTIP")
Share-based payments [Abstract]
Number of tranches \| tranche	2
Vesting period		3 years 3 months
Percentage of grants vested		50.00%
Percentage of remaining grants vested		50.00%
Remaining vesting period		4 years 3 months
Percentage of vesting based on continued service		80.00%
Percentage of vesting based on total shareholder return		20.00%
Number of RSUs granted (in shares)	0
Volume weighted average market price (in dollars per share) \| $ / shares		$ 28
Number of trading days		10 days
Number of consecutive trading days		15 days
2022 Long-Term Incentive Plan Restricted Stock Units ("2022 LTIP") \| Tranche One
Share-based payments [Abstract]
Vesting period	3 years
2022 Long-Term Incentive Plan Restricted Stock Units ("2022 LTIP") \| Tranche Two
Share-based payments [Abstract]
Vesting period	4 years
2023 Long-Term Incentive Plan Restricted Stock Units ("2023 LTIP")
Share-based payments [Abstract]
Number of tranches \| tranche	3
2023 Long-Term Incentive Plan Restricted Stock Units ("2023 LTIP") \| Tranche One \| Time Based Vesting Conditions
Share-based payments [Abstract]
Vesting period	1 year
Number of RSUs issued (in shares)	809,883
2023 Long-Term Incentive Plan Restricted Stock Units ("2023 LTIP") \| Tranche Two \| Time Based Vesting Conditions
Share-based payments [Abstract]
Vesting period	2 years
Number of RSUs issued (in shares)	809,883
2023 Long-Term Incentive Plan Restricted Stock Units ("2023 LTIP") \| Tranche One And Two \| Time Based Vesting Conditions
Share-based payments [Abstract]
Number of tranches \| tranche	2
2023 Long-Term Incentive Plan Restricted Stock Units ("2023 LTIP") \| Tranche Three \| Performance Based Vesting Conditions
Share-based payments [Abstract]
Vesting period	3 years
Number of RSUs issued (in shares)	1,574,725
Daniel Roberts \| 2022 Long-Term Incentive Plan Restricted Stock Units ("2022 LTIP")
Share-based payments [Abstract]
Number of tranches \| tranche		3
Number of RSUs granted (in shares)		305,630
Number of RSUs vested (in shares)		713,166
William Roberts \| 2022 Long-Term Incentive Plan Restricted Stock Units ("2022 LTIP")
Share-based payments [Abstract]
Number of tranches \| tranche		3
Number of RSUs granted (in shares)		305,630
Number of RSUs vested (in shares)		713,166
Non-Executive Director \| 2022 Long-Term Incentive Plan Restricted Stock Units ("2022 LTIP")
Share-based payments [Abstract]
Vesting period		10 days
Number of RSUs vested (in shares)		108,559
Non-Executive Director \| 2023 Long-Term Incentive Plan Restricted Stock Units ("2023 LTIP")
Share-based payments [Abstract]
Vesting period	10 days
Number of RSUs vested (in shares)	120,303
Key Management Personnel \| 2022 Long-Term Incentive Plan Restricted Stock Units ("2022 LTIP")
Share-based payments [Abstract]
Number of RSUs issued (in shares)		1,594,215
Key Management Personnel \| 2023 Long-Term Incentive Plan Restricted Stock Units ("2023 LTIP")
Share-based payments [Abstract]
Number of RSUs issued (in shares)	3,194,491

The number of other equity instruments (ie other than share options) granted in a share-based payment arrangement.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IFRS
-Number 2
-IssueDate 2024-01-01
-Paragraph 45
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=2&code=ifrs-tx-2024-en-r&anchor=para_45&doctype=Standard
-URIDate 2024-03-27

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 2
-IssueDate 2024-01-01
-Paragraph 47
-Subparagraph b
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=2&code=ifrs-tx-2024-en-r&anchor=para_47_b&doctype=Standard
-URIDate 2024-03-27

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The number of other equity instruments (ie other than share options) exercised or vested 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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The number of other equity instruments (i.e other than share options) issued 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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The number of other equity instruments (ie other than share options) vested subject to certain market conditions in a share-based payment arrangement.

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The number of other equity instruments (ie other than share options) vested subject to certain market conditions in a share-based payment arrangement.

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Percentage vesting based on continued service with the group over the vesting period.

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The number of share options vested in a share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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

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