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Share-based compensation - Narrative (Details) - USD ($)		3 Months Ended
	Mar. 12, 2025	Sep. 25, 2026	Sep. 26, 2025	Jun. 26, 2026	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)		1,421,924
Shares withheld to settle employee minimum statutory obligation for applicable income and other employment taxes (in shares)		50,100	69,332
Tax withholdings related to net share settlement of restricted share units		$ 23,910,000	$ 22,697,000
Number of securities called by warrants (in shares)	381,922
Exercise price of warrants or rights (in USD per share)	$ 208.48
Class of warrant or right, warrants vested (in shares)	38,192
Grant date fair value per share (in USD per share)	$ 102.88
Grant date fair value	$ 39,300,000
Warrants outstanding (in shares)		108,862		85,942
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 \| 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 \| Vest on the first of January \| Non-employee director
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting percentage		100.00%
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 \| Vest at the end of the performance period \| Executive of the company \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting percentage		0.00%
Performance share units \| Vest at the end of the performance period \| Executive of the company \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting percentage		100.00%
Equity Incentive Plans \| Restricted share units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized share-based compensation expense		$ 44,800,000
Unrecognized compensation expense, weighted-average period for recognition		1 year 8 months 12 days
Equity Incentive Plans \| Performance share units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized share-based compensation expense		$ 32,600,000
Unrecognized compensation expense, weighted-average period for recognition		1 year 6 months
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
Shares authorized for future issuance (in shares)						160,000