Segment Information - Schedule of Geographical Locations (Details) - EUR (€) € in Thousands	5 Months Ended	7 Months Ended	12 Months Ended
Sep. 30, 2021	Apr. 30, 2021	Sep. 30, 2023	Sep. 30, 2022
Disclosure of geographical areas [line items]
Total revenue	€ 462,664	€ 499,347	€ 1,491,911	€ 1,242,833
Germany
Disclosure of geographical areas [line items]
Total revenue	78,858	66,340	194,884	156,824
United States
Disclosure of geographical areas [line items]
Total revenue	198,634	239,461	712,069	598,438
Rest of world
Disclosure of geographical areas [line items]
Total revenue	€ 185,172	€ 193,546	€ 584,957	€ 487,571

The amount of revenue from contracts with customers. A customer is a party that has contracted with an entity to obtain goods or services that are an output of the entity’s ordinary activities in exchange for consideration.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 15
-IssueDate 2023-01-01
-Paragraph 114
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=15&code=ifrs-tx-2023-en-r&anchor=para_114&doctype=Standard
-URIDate 2023-03-23

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 15
-IssueDate 2023-01-01
-Paragraph 113
-Subparagraph a
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=15&code=ifrs-tx-2023-en-r&anchor=para_113_a&doctype=Standard
-URIDate 2023-03-23

Name:	ifrs-full_RevenueFromContractsWithCustomers
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration