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ORGANIZATION AND NATURE OF OPERATIONS (Details) ¥ in Thousands, $ in Thousands	1 Months Ended						12 Months Ended
	Sep. 30, 2025 CNY (¥) shares	Sep. 30, 2025 USD ($) shares	Mar. 31, 2023 CNY (¥) shares	Mar. 31, 2023 USD ($) shares	Feb. 28, 2023 CNY (¥) shares	Feb. 28, 2023 USD ($) shares	Dec. 31, 2025 CNY (¥)	Dec. 31, 2025 USD ($)	Dec. 31, 2024 CNY (¥)	Dec. 31, 2023 CNY (¥)	Dec. 31, 2021 CNY (¥)	Dec. 31, 2025 USD ($)	Jun. 30, 2021 shares	May 31, 2021 shares
Schedule Of Organization And Nature Of Operations [Line Items]
Cash distribution to shareholders of Shanghai Hesai in connection with the 2021 Reorganization							¥ 292,721	$ 41,859	¥ 0	¥ 17,506
Subscription receivables							0		¥ 292,721			$ 0
IPO \| Class B
Schedule Of Organization And Nature Of Operations [Line Items]
Number of shares issued	22,482,500	22,482,500	10,125,118	10,125,118	10,125,118	10,125,118
Net proceeds from IPO	¥ 4,249,946	$ 4,654,135	¥ 1,225,470	$ 179,786	¥ 1,225,470	$ 179,786
Shanghai Hesai
Schedule Of Organization And Nature Of Operations [Line Items]
Settlement through cash redemption \| ¥											¥ 817,847
Cash distribution to shareholders of Shanghai Hesai in connection with the 2021 Reorganization \| ¥							¥ 292,721			¥ 17,506	¥ 507,620
Shanghai Hesai \| Founding shareholders
Schedule Of Organization And Nature Of Operations [Line Items]
Percentage of equity interest acquired													100.00%
Shanghai Hesai \| Founding shareholders \| Class A
Schedule Of Organization And Nature Of Operations [Line Items]
Number of shares subscribed													30,033,379	30,033,379
Shanghai Hesai \| Existing investors \| Class B
Schedule Of Organization And Nature Of Operations [Line Items]
Number of shares subscribed													62,834,548	62,834,548