Face (par) amount of debt instrument at time of issuance.

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Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

Weighted average interest rate of debt outstanding.

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- Definition

Amount of the cost of borrowed funds accounted for as interest expense.

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The fair value, as of the date of each statement of financial position presented, of securities that are restricted as collateral for the payment of other debt obligations, and that are reclassified and separately reported in the statement of financial position because the transferee has the right by contract or custom to sell or re-pledge them.

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- Definition

Amount of cash restricted as to withdrawal or usage, classified as current. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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SHORT-TERM LOAN- Additional information (Details) ¥ in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2020 USD ($)	Dec. 31, 2020 CNY (¥)	Dec. 31, 2018 CNY (¥)	Dec. 31, 2020 CNY (¥)	Dec. 31, 2019 CNY (¥)
Short-term Debt [Line Items]
Amount of borrowings				¥ 600,000
Weighted average interest rate	3.09%			3.09%
Assets collateralized				¥ 400,000
Principal amount				600,000
Bank deposit classified as restricted cash	$ 9,163			59,791	¥ 1,480
Interest expenses	$ 1,813	¥ 11,830	¥ 3,122
Bank Time Deposits
Short-term Debt [Line Items]
Assets collateralized				¥ 400,000
Minimum
Short-term Debt [Line Items]
Borrowing term	6 months	6 months
Maximum
Short-term Debt [Line Items]
Borrowing term	1 year	1 year