Summary of significant accounting policies - Schedule of Estimated Useful Lives (Details)	Dec. 31, 2025
Leasehold improvements
Property, Equipment and Software
Estimated useful lives	us-gaap:UsefulLifeShorterOfTermOfLeaseOrAssetUtilityMember
Computers and electronic equipment \| Minimum
Property, Equipment and Software
Estimated useful lives	3 years
Computers and electronic equipment \| Maximum
Property, Equipment and Software
Estimated useful lives	5 years
Mechanical equipment
Property, Equipment and Software
Estimated useful lives	5 years
Mining equipment
Property, Equipment and Software
Estimated useful lives	1 year 6 months
Motor vehicles
Property, Equipment and Software
Estimated useful lives	5 years
Software
Property, Equipment and Software
Estimated useful lives	3 years

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.

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

+ Details

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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.

+ Details

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- Definition

Indicates description of term of useful life for property, plant, and equipment when not stated as numeric value.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 360
-SubTopic 10
-Name Accounting Standards Codification
-Section 35
-Paragraph 3
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482190/360-10-35-3

+ Details

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- Details

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