Summary of Significant Accounting Policies - Property, plant and equipment, net (Details)	Dec. 31, 2024
Buildings
Property, plant and equipment, net
Useful lives	30 years
Motor vehicles \| Minimum
Property, plant and equipment, net
Useful lives	3 years
Motor vehicles \| Maximum
Property, plant and equipment, net
Useful lives	10 years
Production facilities \| Minimum
Property, plant and equipment, net
Useful lives	5 years
Production facilities \| Maximum
Property, plant and equipment, net
Useful lives	10 years
Mold and tooling \| Minimum
Property, plant and equipment, net
Useful lives	3 years
Mold and tooling \| Maximum
Property, plant and equipment, net
Useful lives	7 years
Electronic devices, furniture and office equipment \| Minimum
Property, plant and equipment, net
Useful lives	2 years
Electronic devices, furniture and office equipment \| Maximum
Property, plant and equipment, net
Useful lives	5 years
Leasehold improvements
Property, plant and equipment, net
Property, Plant, and Equipment, Useful Life, Term, Description [Extensible Enumeration]	us-gaap:UsefulLifeShorterOfTermOfLeaseOrAssetUtilityMember

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

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+ References

No definition available.

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+ 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

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