PRINCIPLES OF CONSOLIDATION (Details) - CNY (¥) ¥ in Thousands	9 Months Ended
Sep. 30, 2017	Sep. 30, 2016
Variable interest entity information
Net revenue	¥ 1,110,690	¥ 744,291
Net income (loss)	(210,357)	(206,773)
Net cash provided by (used in) operating activities	(161,056)	(122,570)
Net cash used in investing activities	(1,229,408)	(863,792)
Net cash provided by (used in) financing activities	805,108	847,322
VIEs
Variable interest entity information
Net revenue	1,010,033	413,567
Net income (loss)	(9,024)	44,014
Net cash provided by (used in) operating activities	(20,925)	59,018
Net cash used in investing activities	(65,437)	(83,804)
Net cash provided by (used in) financing activities	(109,588)	277,018
Costs for outsourcing and other services provided by other entities within the Company	¥ 548,902	¥ 189,715

Cost incurred for outsourcing and other services provided by other entities.

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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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The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.

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Total revenue from sale of goods and services rendered during the reporting period, in the normal course of business, reduced by sales returns and allowances, and sales discounts.

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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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