Accounts and notes receivable, net (Details) ¥ in Thousands, $ in Thousands	Dec. 31, 2023 CNY (¥)	Dec. 31, 2023 USD ($)	Dec. 31, 2022 CNY (¥)
Accounts and notes receivable, net
Accounts receivable	¥ 63,508		¥ 51,582
Allowance for doubtful accounts	(3,026)		(201)
Accounts and notes receivable, net	¥ 60,482	$ 8,519	¥ 51,381

Amount, before allowance for credit loss, of right to consideration from customer for product sold and service rendered in normal course of business, classified as current.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(3)(a)(1))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480566/210-10-S99-1

Reference 2: http://www.xbrl.org/2003/role/exampleRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483467/210-10-45-1

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481990/310-10-45-2

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 9
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481990/310-10-45-9

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant