SIGNIFICANT ACCOUNTING POLICIES - Income taxes (Details) - CNY (¥)	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Income taxes
Unrecognized tax benefits accrued for interest and penalties	¥ 0	¥ 0	¥ 0
Uncertain tax positions	¥ 2,240,000,000

Amount of unrecognized tax benefits.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 45
-Paragraph 10B
-URI https://asc.fasb.org/extlink&oid=123427490&loc=SL37586934-109318

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 15A
-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=121826272&loc=SL6600010-109319

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