SIGNIFICANT RELATED PARTY BALANCES AND TRANSACTIONS - Compensation of directors, supervisors and senior management (Details) - CNY (¥) ¥ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Significant related party transactions
Fees	¥ 683	¥ 780	¥ 756
Basic salaries, housing fund, other allowances and benefits in kind	4,183	4,665	1,849
Pension costs	20	513	234
Total remuneration	4,886	5,958	2,839
Directors, supervisors and senior management
Significant related party transactions
Fees	683	780	756
Basic salaries, housing fund, other allowances and benefits in kind	6,081	6,945	3,953
Pension costs	30	715	482
Total remuneration	¥ 6,794	¥ 8,440	¥ 5,191

The amount of compensation to key management personnel in the form of fees.

No definition available.

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- Definition

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+ References

No definition available.

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- Definition

The amount of compensation to key management personnel. [Refer: Key management personnel of entity or parent [member]]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition

The amount of compensation to key management personnel in the form of post-employment benefits. [Refer: Key management personnel of entity or parent [member]]

+ References

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- Definition

The amount of compensation to key management personnel in the form of short-term employee benefits. [Refer: Key management personnel of entity or parent [member]]

+ References

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