Inventories - Schedule of Inventories (Details) ¥ in Thousands, $ in Thousands	Dec. 31, 2023 CNY (¥)	Dec. 31, 2023 USD ($)	Dec. 31, 2022 CNY (¥)	Dec. 31, 2021 CNY (¥)
Inventories
Finished goods	¥ 117,665		¥ 123,672
Raw materials	27,185		7,229
Inventories	144,850	$ 20,402	130,901
Write-downs of inventories	¥ 35,695		¥ 179,694	¥ 89,071

Amount of inventory reserves for last-in first-out (LIFO) and other inventory valuation methods.

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Amount before valuation and LIFO reserves of completed merchandise or goods expected to be sold within one year or operating cycle, if longer.

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Amount after valuation and LIFO reserves of inventory expected to be sold, or consumed within one year or operating cycle, if longer.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 852
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Gross amount of unprocessed materials to be used in manufacturing or production process and supplies that will be consumed.

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