PARENT COMPANY ONLY CONDENSED FINANCIAL INFORMATION (Condensed statements of cash flows) (Details) ¥ in Thousands, $ in Thousands	12 Months Ended
Dec. 31, 2017 CNY (¥)	Dec. 31, 2017 USD ($)	Dec. 31, 2016 CNY (¥)	Dec. 31, 2015 CNY (¥)
Condensed Financial Statements, Captions [Line Items]
Net cash used in operating activities	¥ 26,732	$ 4,108	¥ (78,078)	¥ (175,138)
Net cash (used in) generated from investing activities	(313,010)	(48,109)	(74,847)	(391,083)
Net cash generated from (used in) financing activities	194,405	29,881	(131,370)	590,398
Exchange rate effect on cash	159	24	(11,240)	(17,419)
Net (decrease) increase in cash	(91,714)	(14,096)	(295,535)	6,758
Cash at beginning of year	189,905	29,188	485,440	478,682
Cash at end of year	98,191	15,092	189,905	485,440
Parent Company [Member]
Condensed Financial Statements, Captions [Line Items]
Net cash used in operating activities	(89,751)	(13,794)	(5,230)	(29,140)
Net cash (used in) generated from investing activities	(21,452)	(3,297)	785,513	(354,246)
Net cash generated from (used in) financing activities	127,106	19,535	(748,076)	196,366
Exchange rate effect on cash	(35,021)	(5,383)	(11,757)	13,663
Net (decrease) increase in cash	(19,118)	(2,939)	20,450	(173,357)
Cash at beginning of year	22,218	3,415	1,768	175,125
Cash at end of year	¥ 3,104	$ 477	¥ 22,218	¥ 1,768

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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
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Amount of increase (decrease) in cash. Cash is 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. Includes effect from exchange rate changes.

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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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