Short-term borrowings - Schedule of short-term borrowings (Details) ¥ in Thousands, $ in Thousands	Dec. 31, 2023 CNY (¥)	Dec. 31, 2023 USD ($)	Dec. 31, 2022 CNY (¥)
Short-term borrowings
Short-term borrowings	¥ 1,200,000	$ 169,016	¥ 870,000
Unsecured bank loans
Short-term borrowings
Short-term borrowings	¥ 1,200,000		¥ 870,000

Reflects the total carrying amount as of the balance sheet date of debt having initial terms less than one year or the normal operating cycle, if longer.

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Name:	us-gaap_ShortTermBorrowings
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant