Organization and principal activities (Details)	12 Months Ended
Dec. 31, 2022
Business Operation Agreement
Variable interest entity
Threshold period of written notice required to terminate the agreement	30 days
Term (in years)	P10Y
Exclusive Option Agreements
Variable interest entity
Threshold period of written notice required to terminate the agreement	10 years

Description of the terms of arrangements, giving consideration to both explicit arrangements and implicit variable interests, that could require the reporting entity to provide financial support (for example, liquidity arrangements and obligations to purchase assets) to the Variable Interest Entity (VIE), including events or circumstances that could expose the reporting entity to a loss.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (d)
-URI https://asc.fasb.org/extlink&oid=123419778&loc=d3e5710-111685

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (c)
-URI https://asc.fasb.org/extlink&oid=123419778&loc=d3e5728-111685

Name:	us-gaap_VariableInterestEntityTermsOfArrangements
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration