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Share-based compensation - Narrative (Details) - USD ($)	3 Months Ended	6 Months Ended
	Dec. 29, 2023	Dec. 29, 2023	Dec. 30, 2022	Dec. 12, 2019	Nov. 02, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation costs capitalized	$ 0		$ 0
Number of ordinary shares available for future grant (in shares)	1,870,190	1,870,190
Shares withheld to settle employee minimum statutory obligation for applicable income and other employment taxes (in shares)		100,763	165,502
Tax withholdings related to net share settlement of restricted share units		$ 12,352,000	$ 16,796,000
Restricted share units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized share-based compensation expense	$ 19,600,000	$ 19,600,000
Unrecognized compensation expense, weighted-average period for recognition		2 years 8 months 12 days
Restricted share units \| Vesting option one
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award granted vesting period, year		3 years
Restricted share units \| Vesting option two
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award granted vesting period, year		4 years
Restricted share units \| Non-employee director
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award granted vesting period, year		1 year
Restricted share units \| Non-employee director \| Vest on the first of January
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting percentage		100.00%
Performance share units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized share-based compensation expense	$ 12,600,000	$ 12,600,000
Unrecognized compensation expense, weighted-average period for recognition		1 year 3 months 18 days
Performance share units \| Executive of the Company
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award granted vesting period, year		2 years
Performance share units \| Executive of the Company \| Vest at the end of the performance period \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting percentage		0.00%
Performance share units \| Executive of the Company \| Vest at the end of the performance period \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting percentage		100.00%
Equity Incentive 2020 plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of ordinary shares available for future grant (in shares)				1,700,000
Shares reserved for future issuance (in shares)				1,300,000
Shares authorized for future issuance (in shares)				1,281,619
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	111,347
Shares authorized for future issuance (in shares)					160,000