v3.25.3
Related Party Disclosures - Additional Information (Details)
$ in Millions
 12 Months Ended
May 30, 2025
shares
Oct. 10, 2023
shares
Sep. 30, 2025
EUR (€)
shares
Sep. 30, 2024
EUR (€)
Sep. 30, 2024
USD ($)
Sep. 30, 2023
EUR (€)
Oct. 13, 2023
shares
Disclosure of transactions between related parties [line items]              
Non-employee director cash compensation per year     € 300,000 € 300,000      
Right of use Assets     € 179,762,000 171,334,000      
Ordinary Shares              
Disclosure of transactions between related parties [line items]              
Shares issued | shares             10,752,688
Shares repurchased of ordinary shares | shares 3,927,344 5,648,465 3,927,344        
Shares repurchased amount of ordinary shares     € 176,400,000        
Restricted share units [member]              
Disclosure of transactions between related parties [line items]              
Expenses recognized during period     300,000 300,000      
Ockenfels              
Disclosure of transactions between related parties [line items]              
Lease payments     500,000 500,000   € 500,000  
Lease liability     900,000 1,300,000      
Right of use Assets     800,000 1,200,000      
Related party transactions income     100,000 0   0  
Outstanding receivables     9,800,000 9,800,000      
Outstanding payables     1,800,000 1,800,000      
Management Investment Plan              
Disclosure of transactions between related parties [line items]              
Paid personal income taxes for the fully vested program       11,400,000 $ 12.6    
Other related parties [member]              
Disclosure of transactions between related parties [line items]              
Director compensation     500,000 500,000      
Consulting fees and cost reimbursements     200,000 300,000   400,000  
Sales     700,000 700,000   2,300,000  
Marketing expenses     100,000 100,000   € 200,000  
Lease liability     800,000 200,000      
Right of use Assets     700,000 200,000      
TRA liability     € 356,760,000 € 359,890,000