SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Inventories (Details) ¥ in Millions, $ in Millions	12 Months Ended
Dec. 31, 2025 CNY (¥)	Dec. 31, 2025 USD ($)	Dec. 31, 2024 CNY (¥)
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
Inventory reserves	¥ 69.0	$ 9.8	¥ 56.2

Amount of loss from reductions in inventory due to subsequent measurement adjustments, including, but not limited to, physical deterioration, obsolescence, or changes in price levels.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 330
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483080/330-10-50-2

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Balance Type:	debit
Period Type:	duration