PRINCIPAL ACCOUNTING POLICIES - Supplemental cash flow information related to operating leases (Details) ¥ in Thousands	12 Months Ended
Dec. 31, 2020 CNY (¥)
PRINCIPAL ACCOUNTING POLICIES
Cash payments	¥ 48,890
New operating lease assets obtained in exchange for operating lease liabilities	¥ 24,688
weighted average remaining lease term	3 years 1 month 13 days
weighted average discount rate	4.80%

No definition available.

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- Definition

Amount of cash outflow from operating lease, excluding payments to bring another asset to condition and location necessary for its intended use.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
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-Section 45
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- Definition

Weighted average discount rate for operating lease calculated at point in time.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Weighted average remaining lease term for operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
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- Definition

Amount of increase in right-of-use asset obtained in exchange for operating lease liability.

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-Publisher FASB
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