LONG-TERM INVESTMENTS - Schedule of Investments under equity method (Details) ¥ in Thousands, $ in Thousands	12 Months Ended
Dec. 31, 2021 CNY (¥)	Dec. 31, 2020 CNY (¥)	Dec. 31, 2021 USD ($)	Dec. 31, 2019 CNY (¥)
Equity method investments	¥ 31,779	¥ 58,479		¥ 36,588
Equity securities accounted for under alternative measurement	196,296	5,900
Equity securities with readily determinable fair value	153,326	94,552
Total long-term investments	¥ 381,401	¥ 158,931	$ 59,850

This item represents an other than temporary decline in value that has been recognized against an investment accounted for under the equity method of accounting. The excess of the carrying amount over the fair value of the investment represents the amount of the write down which is or was reflected in earnings. The written down value is a new cost basis with the adjusted value of the investment becoming its new carrying value subject to the equity accounting method. Evidence of a loss in value might include, but would not necessarily be limited to, absence of an ability to recover the carrying amount of the investment or inability of the investee to sustain an earnings capacity which would justify the carrying amount of the investment.

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This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

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- Definition

Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI), classified as current.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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The total amount of investments that are intended to be held for an extended period of time (longer than one operating cycle).

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