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Summary of significant accounting policies - Schedule of Estimated Useful Lives of Property, Plant and Equipment (Details)	Sep. 30, 2025
Buildings
Property, Plant and Equipment [Line Items]
Property, plant and equipment, estimated useful lives	40 years
Furniture and fixtures
Property, Plant and Equipment [Line Items]
Property, plant and equipment, estimated useful lives	4 years
Computer equipment and servers
Property, Plant and Equipment [Line Items]
Property, plant and equipment, estimated useful lives	4 years
Plant, machinery and equipment
Property, Plant and Equipment [Line Items]
Property, plant and equipment, estimated useful lives	4 years
Computer software | Minimum
Property, Plant and Equipment [Line Items]
Property, plant and equipment, estimated useful lives	4 years
Computer software | Maximum
Property, Plant and Equipment [Line Items]
Property, plant and equipment, estimated useful lives	7 years
Leasehold improvements | Maximum
Property, Plant and Equipment [Line Items]
Property, plant and equipment, estimated useful lives	10 years
Vehicles | Minimum
Property, Plant and Equipment [Line Items]
Property, plant and equipment, estimated useful lives	3 years
Vehicles | Maximum
Property, Plant and Equipment [Line Items]
Property, plant and equipment, estimated useful lives	4 years

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 842
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 7A
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478964/842-20-50-7A

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- Definition

Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

+ References

No definition available.

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