PREPAID EXPENSES AND OTHER CURRENT ASSETS - Analysis of the allowance for doubtful debt in relation to other receivables (Details) - CNY (¥) ¥ in Thousands	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022
Analysis of the allowance for doubtful debt in relation to other receivables
Balance at beginning of the year	¥ 131,624	¥ 130,908
Addition	313,993	15,460
Write-off		(15,000)
Foreign exchange difference	52	256
Balance at the end of the year	¥ 445,669	¥ 131,624

Amount of expense related to other loss.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 45
-Paragraph 28
-Subparagraph (a)
-SubTopic 10
-Topic 230
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482740/230-10-45-28

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 220
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03(5))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483621/220-10-S99-2

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 942
-SubTopic 220
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04(14))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483589/942-220-S99-1

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