Loans and Borrowings - Schedule of Principal and Interest Payable Outstanding Amounts (Details) - EUR (€) € in Thousands	6 Months Ended
Mar. 31, 2024	Sep. 30, 2023
Disclosure of detailed information about borrowings [line items]
Senior Note embedded derivative	€ 28,638	€ 28,638
Less: amortization under the effective interest method	(34,828)	(46,163)
Non-current liabilities	1,298,763	1,815,695
Current liabilities	€ 29,105	37,343
Term Loan \| EUR
Disclosure of detailed information about borrowings [line items]
Borrowings, maturity	2028
Non-current liabilities, gross	€ 375,000	375,000
Term Loan \| USD
Disclosure of detailed information about borrowings [line items]
Borrowings, maturity	2028
Non-current liabilities, gross	€ 301,893	730,159
Current liabilities	€ 3,038	7,347
Vendor Loan \| EUR
Disclosure of detailed information about borrowings [line items]
Borrowings, maturity	2029
Non-current liabilities, gross	€ 199,560	299,560
Senior Notes \| EUR
Disclosure of detailed information about borrowings [line items]
Borrowings, maturity	2029
Non-current liabilities, gross	€ 428,500	428,500
Term Loan interest payable
Disclosure of detailed information about borrowings [line items]
Current liabilities	1,304,953	1,833,220
Term Loan interest payable \| EUR
Disclosure of detailed information about borrowings [line items]
Current liabilities	4,244	4,197
Term Loan interest payable \| USD
Disclosure of detailed information about borrowings [line items]
Current liabilities	4,422	10,938
Vendor Loan interest payable \| EUR
Disclosure of detailed information about borrowings [line items]
Current liabilities	8,028	5,487
Senior Notes interest payable \| EUR
Disclosure of detailed information about borrowings [line items]
Non-current liabilities	1,298,763
Current liabilities	€ 9,373	€ 9,373

Amortization of borrowings.

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- Definition

Long term borrowings, gross.

+ References

No definition available.

+ Details

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- Definition

Senior notes embedded derivative amount.

+ References

No definition available.

+ Details

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- Definition

The maturity of borrowings. [Refer: Borrowings]

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IFRS
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-IssueDate 2023-01-01
-Paragraph 7
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-URIDate 2023-03-23

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- Definition

Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with members defined in one or many axes of the table.

+ References

No definition available.

+ Details

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- Definition

The non-current portion of non-current borrowings. [Refer: Borrowings]

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
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-IssueDate 2023-01-01
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-URIDate 2023-03-23

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- Definition

The amount of current borrowings. [Refer: Borrowings]

+ References

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