Loans and Borrowings - Schedule of Principal and Interest Payable Outstanding Amounts (Details) - EUR (€) € in Thousands	12 Months Ended
Sep. 30, 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	(23,361)	(46,162)
Non-current liabilities	1,169,965	1,815,695
Current liabilities	€ 24,670	37,343
Original Term Loan \| EUR
Disclosure of detailed information about borrowings [line items]
Borrowings, maturity	2028
Non-current liabilities, gross		375,000
Original Term Loan \| USD
Disclosure of detailed information about borrowings [line items]
Borrowings, maturity	2028
Non-current liabilities, gross		730,159
Current liabilities		7,347
New Term Loan \| EUR
Disclosure of detailed information about borrowings [line items]
Borrowings, maturity	2029
Non-current liabilities, gross	€ 375,000
New Term Loan \| USD
Disclosure of detailed information about borrowings [line items]
Borrowings, maturity	2029
Non-current liabilities, gross	€ 152,883
Current liabilities	€ 7,890
Vendor Loan \| EUR
Disclosure of detailed information about borrowings [line items]
Borrowings, maturity	2029
Non-current liabilities, gross	€ 208,305	299,560
Senior Notes \| EUR
Disclosure of detailed information about borrowings [line items]
Borrowings, maturity	2029
Non-current liabilities, gross	€ 428,500	428,500
Original Term Loan interest payable \| EUR
Disclosure of detailed information about borrowings [line items]
Current liabilities		4,197
Original Term Loan interest payable \| USD
Disclosure of detailed information about borrowings [line items]
Current liabilities		10,938
New Term Loan interest payable \| EUR
Disclosure of detailed information about borrowings [line items]
Current liabilities	3,591
Term Loan interest payable
Disclosure of detailed information about borrowings [line items]
Non-current liabilities, gross	1,164,688	1,833,219
Vendor Loan interest payable \| EUR
Disclosure of detailed information about borrowings [line items]
Current liabilities	3,816	5,488
Senior Notes interest payable \| EUR
Disclosure of detailed information about borrowings [line items]
Current liabilities	€ 9,373	€ 9,373

Amortization of borrowings.

No definition available.

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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
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-IssueDate 2024-01-01
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-URIDate 2024-03-27

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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.

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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 2024-01-01
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-URIDate 2024-03-27

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- Definition

The amount of current borrowings. [Refer: Borrowings]

+ References

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