The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(ii)
-URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(i)
-URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901

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- Definition

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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- Definition

The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901

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Share-based compensation - Share-based award activity (Details) - shares	Mar. 31, 2023	Jun. 24, 2022	Mar. 25, 2022	Jun. 25, 2021
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of ordinary shares available for future grant (in shares)	2,069,550
2020 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of ordinary shares available for future grant (in shares)	1,958,203
2010 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of ordinary shares available for future grant (in shares)	0
2017 Inducement Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of ordinary shares available for future grant (in shares)	111,347
Restricted share units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share units outstanding (in shares)	374,038	459,626	460,928	641,875
Restricted share units \| 2020 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share units outstanding (in shares)	343,211
Restricted share units \| 2010 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share units outstanding (in shares)	30,827
Restricted share units \| 2017 Inducement Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share units outstanding (in shares)	0
Performance share units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share units outstanding (in shares)	204,016	285,882	285,882	427,028
Performance share units \| 2020 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share units outstanding (in shares)	204,016
Performance share units \| 2010 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share units outstanding (in shares)	0
Performance share units \| 2017 Inducement Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share units outstanding (in shares)	0