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Number of shares sold

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No definition available.

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Offering price per ordinary share and accompanying warrant

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The percentage of ownership interest held.

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Related party transactions, expense for director services

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Related party transactions, expense for professional services

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Related party transactions, expense for secretarial and accounting services

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- Definition

The amounts payable resulting from related party transactions. [Refer: Related parties [member]]

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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The amount of outstanding funds that the entity is obligated to repay.

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The interest rate on borrowings. [Refer: Borrowings]

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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.

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The amount of interest expense on borrowings. [Refer: Interest expense; Borrowings]

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Related party transactions (Details)		12 Months Ended
Related party transactions (Details)	Sep. 12, 2023 $ / shares shares	Sep. 30, 2023 USD ($) $ / shares	Sep. 30, 2022 USD ($)	Sep. 30, 2021 USD ($)	Sep. 30, 2020 USD ($)	Sep. 03, 2021 $ / shares	Aug. 20, 2021 GBP (£)
Disclosure of transactions between related parties [line items]
Exercise price, warrants \| $ / shares						$ 11.50
Heritage Assets SCSP, Ropemaker Nominees Limited and Carlo Calabria
Disclosure of transactions between related parties [line items]
Number of shares sold \| shares	7,935,164
Number of shares purchasable on exercise of warrants issued \| shares	7,935,164
Offering price per ordinary share and accompanying warrant \| $ / shares	$ 0.78
Heritage Assets SCSP, Ropemaker Nominees Limited and Carlo Calabria \| 2023 Investor warrants
Disclosure of transactions between related parties [line items]
Exercise price, warrants \| $ / shares		$ 0.78
Arqit PTE
Disclosure of transactions between related parties [line items]
Related party transactions, expense for secretarial and accounting services		$ 0	$ 5,091	$ 11,679
Arqit PTE \| David Williams
Disclosure of transactions between related parties [line items]
Percentage of ownership interest held		50
Amounts payable, related party transactions			6,574
Related party transaction loans \| £							£ 2,000,000
Borrowings interest rate							8.00%
Interest paid on borrowings				14,401	$ 0
Fee charged on borrowings				88,800	0
Arqit PTE \| David Bestwick
Disclosure of transactions between related parties [line items]
Percentage of ownership interest held		50
Related party transaction loans \| £							£ 2,000,000
Borrowings interest rate							8.00%
Interest paid on borrowings				14,401	0
Fee charged on borrowings				88,800	0
Arqit PTE \| Lt General VL Jamieson
Disclosure of transactions between related parties [line items]
Related party transactions, expense for director services		$ 100,000	113,923	103,861
Arqit PTE \| General S Wilson
Disclosure of transactions between related parties [line items]
Related party transactions, expense for director services		$ 100,000	100,575	73,398
Arqit PTE \| Notion Capital
Disclosure of transactions between related parties [line items]
Related party transactions, expense for professional services			$ 0	$ 1,750	$ 0