ADDITIONAL INFORMATION - CONDENSED FINANCIAL STATEMENTS (Schedule of Information of Consolidating Statement of Cash Flows) (Details) ¥ in Thousands, $ in Thousands	12 Months Ended
Dec. 31, 2018 CNY (¥)	Dec. 31, 2018 USD ($)	Dec. 31, 2017 CNY (¥)	Dec. 31, 2016 CNY (¥)
Statements of Cash Flows [Line Items]
Cash flows from operating activities	¥ 25,445	$ 3,699	¥ 20,210	¥ 17,535
Cash flows from investing activities	(28,520)	(4,148)	(61,078)	(65,218)
Cash flows from financing activities	46,872	6,817	39,205	(1,504)
Cash and cash equivalents at beginning of year	195,303		196,900
Cash and cash equivalents at end of year	211,436	30,752	195,303	196,900
Parent Company [Member]
Statements of Cash Flows [Line Items]
Cash flows from operating activities	(86)	(13)	(18,255)	(6,348)
Cash flows from investing activities	(2,619)	(381)	(1,556)	0
Cash flows from financing activities	7,476	1,087	18,667	(843)
Effects of exchange rate changes on cash and cash equivalents	0	0	0	0
Net change in cash and cash equivalents	4,771	693	(1,144)	(7,191)
Cash and cash equivalents at beginning of year	323	47	1,467	8,658
Cash and cash equivalents at end of year	¥ 5,094	$ 740	¥ 323	¥ 1,467

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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. Excludes cash and cash equivalents within disposal group and discontinued operation.

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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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