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CONVERTIBLE REDEEMABLE PREFERRED SHARES - Narratives (Details) ¥ in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2025 CNY (¥)	Dec. 31, 2025 USD ($)	Dec. 31, 2024 CNY (¥)	Dec. 31, 2023 CNY (¥)	Dec. 31, 2021 CNY (¥)	Apr. 30, 2025
CONVERTIBLE REDEEMABLE PREFERRED SHARES
Preferred stock, redemption simple interest (%)					12.00%
Preferred stock, initial conversion ratio				1		1
Payments for offering expenses	¥ 36,272	$ 5,186	¥ 10,091
Series A preferred stock
CONVERTIBLE REDEEMABLE PREFERRED SHARES
Preferred stock, dividend rate (%)					8.00%
Payments for offering expenses					¥ 300
Series B preferred stock
CONVERTIBLE REDEEMABLE PREFERRED SHARES
Preferred stock, dividend rate (%)					8.00%
Payments for offering expenses					¥ 3,100
Series B+ Preferred Shares
CONVERTIBLE REDEEMABLE PREFERRED SHARES
Preferred stock, dividend rate (%)	8.00%	8.00%
Payments for offering expenses				¥ 0

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- Definition

Percentage of simple interest used for calculating the preferred stock redemption price.

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The cash outflow for cost incurred directly with the issuance of an equity security.

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Number of common shares issuable upon conversion for each share of preferred stock to be converted.

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- Definition

The percentage rate used to calculate dividend payments on preferred stock.

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