ADDITIONAL INFORMATION - CONDENSED FINANCIAL STATEMENTS - Consolidating Statement of Cash Flows (Details) ¥ in Thousands, $ in Thousands	12 Months Ended
Dec. 31, 2020 USD ($)	Dec. 31, 2020 CNY (¥)	Dec. 31, 2019 CNY (¥)	Dec. 31, 2018 CNY (¥)
Statements of Cash Flows [Line Items]
Cash flows from operating activities	$ 738	¥ 4,812	¥ (10,210)	¥ 25,445
Cash flows from investing activities	(15,097)	(98,513)	(33,153)	(28,520)
Cash flows from financing activities	8,456	55,172	(40,620)	46,872
Cash, cash equivalents and restricted cash at beginning of year	24,151	157,600	241,508	197,653
Cash, cash equivalents and restricted cash at end of year	18,336	119,645	157,600	241,508
Reportable Legal Entities [Member] \| Parent Company [Member]
Statements of Cash Flows [Line Items]
Cash flows from operating activities	(2,193)	(14,319)	57,044	(86)
Cash flows from investing activities	(20)	(133)		(2,619)
Cash flows from financing activities	2,150	14,026	(61,485)	7,476
Net change in cash and cash equivalents	(63)	(426)	(4,441)	4,771
Cash, cash equivalents and restricted cash at beginning of year	98	653	5,094	323
Cash, cash equivalents and restricted cash at end of year	$ 35	¥ 227	¥ 653	¥ 5,094

No definition available.

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Amount of increase (decrease) in cash and cash equivalents. Cash and cash equivalents are the amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Includes effect from exchange rate changes.

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Amount of cash and cash equivalents, and cash and cash equivalents restricted to withdrawal or usage. Excludes amount for disposal group and discontinued operations. 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. Cash equivalents include, but are not limited to, short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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Amount of cash inflow (outflow) from financing activities, including discontinued operations. Financing activity cash flows include obtaining resources from owners and providing them with a return on, and a return of, their investment; borrowing money and repaying amounts borrowed, or settling the obligation; and obtaining and paying for other resources obtained from creditors on long-term credit.

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Amount of cash inflow (outflow) from investing activities, including discontinued operations. Investing activity cash flows include making and collecting loans and acquiring and disposing of debt or equity instruments and property, plant, and equipment and other productive assets.

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Amount of cash inflow (outflow) from operating activities, including discontinued operations. Operating activity cash flows include transactions, adjustments, and changes in value not defined as investing or financing activities.

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