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The aggregate costs incurred for design and development expenses during the reporting period charged as research and development.

No definition available.

Name:	nio_ResearchAndDevelopmentExpenseDesignAndDevelopment
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The aggregate costs incurred for employee compensation during the reporting period charged as research and development.

No definition available.

Name:	nio_ResearchAndDevelopmentExpenseEmployeeCompensation
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The aggregate costs incurred for others during the reporting period charged as research and development.

No definition available.

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The aggregate costs incurred for rental and related expenses during the reporting period charged as research and development.

No definition available.

Name:	nio_ResearchAndDevelopmentExpenseRentalAndRelatedExpenses
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The aggregate costs incurred for travel expenses during the reporting period charged as research and development.

No definition available.

Name:	nio_ResearchAndDevelopmentExpenseTravelExpenses
Namespace Prefix:	nio_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

Amount of expense for research and development. Includes, but is not limited to, cost for computer software product to be sold, leased, or otherwise marketed and writeoff of research and development assets acquired in transaction other than business combination or joint venture formation or both. Excludes write-down of intangible asset acquired in business combination or from joint venture formation or both, used in research and development activity.

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 48
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482785/280-10-55-48

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 985
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481283/985-20-50-2

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 730
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482916/730-10-50-1

Reference 4: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 912
-SubTopic 730
-Name Accounting Standards Codification
-Section 25
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479532/912-730-25-1

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- References

No definition available.