Taxation - Income tax holiday tax rate (Details) - CNY (¥) ¥ / shares in Units, ¥ in Thousands	12 Months Ended
Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Reconciliations of the income tax expenses
Tax effect of taxexempt entity and preferential tax rate	¥ 797,326	¥ 1,613,371	¥ 321,507
Effect of tax holiday on basic net income per share	¥ 0.4	¥ 0.82	¥ 0.17
Effect of tax holiday on diluted net income per share	¥ 0.37	¥ 0.76	¥ 0.17

Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to income exempt from income tax because of a tax holiday.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 12A
-Subparagraph (b)(1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482685/740-10-50-12A

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 12
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482685/740-10-50-12

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration