FAIR VALUE MEASUREMENT (Details 3) - CNY (¥) ¥ in Millions	9 Months Ended	12 Months Ended
Sep. 30, 2015	Dec. 31, 2014
Dining Secretary
Significant unobservable inputs used in the valuation
Loss from impairment of long-term investment (Note 9)		¥ 33
Dining Secretary \| Discounted cash flow
Significant unobservable inputs used in the valuation
WACC (as a percent)	27.94%
Terminal growth rate (as a percent)	3.00%
LoMD (as a percent)	25.00%
Dining Secretary \| Option pricing model
Significant unobservable inputs used in the valuation
Time to liquidation	3 years 4 days
Risk-free rate (as a percent)	4.13%
Expected volatility (as a percent)	41.40%
Dividend yield (as a percent)	0.00%
Dining Secretary \| Option pricing model \| Liquidation scenario
Significant unobservable inputs used in the valuation
Probability (as a percent)	45.00%
Dining Secretary \| Option pricing model \| Redemption scenario
Significant unobservable inputs used in the valuation
Probability (as a percent)	45.00%
Dining Secretary \| Option pricing model \| IPO scenario
Significant unobservable inputs used in the valuation
Probability (as a percent)	10.00%
Happy City \| Option pricing model \| Liquidation scenario
Significant unobservable inputs used in the valuation
Probability (as a percent)	50.00%
Happy City \| Option pricing model \| Redemption scenario
Significant unobservable inputs used in the valuation
Probability (as a percent)	50.00%
Available-for-sale securities. \| Tujia and LY.com \| Discounted cash flow
Significant unobservable inputs used in the valuation
WACC (as a percent)	19.00%
Terminal growth rate (as a percent)	3.00%
LoMD (as a percent)	28.00%
Available-for-sale securities. \| Tujia and LY.com \| Option pricing model
Significant unobservable inputs used in the valuation
Time to liquidation	3 years
Risk-free rate (as a percent)	3.43%
Expected volatility (as a percent)	50.89%
Dividend yield (as a percent)	0.00%
Available-for-sale securities. \| Tujia and LY.com \| Option pricing model \| Liquidation scenario
Significant unobservable inputs used in the valuation
Probability (as a percent)	20.00%
Available-for-sale securities. \| Tujia and LY.com \| Option pricing model \| Redemption scenario
Significant unobservable inputs used in the valuation
Probability (as a percent)	80.00%
Available-for-sale securities. \| Dining Secretary
Significant unobservable inputs used in the valuation
Loss from impairment of long-term investment (Note 9)		33
Reversal of prior recognized unrealized loss		¥ 4
Available-for-sale securities. \| Happy City \| Discounted cash flow
Significant unobservable inputs used in the valuation
WACC (as a percent)	27.67%
Terminal growth rate (as a percent)	3.00%
LoMD (as a percent)	25.00%
Available-for-sale securities. \| Happy City \| Option pricing model
Significant unobservable inputs used in the valuation
Time to liquidation	2 years 8 months 1 day
Risk-free rate (as a percent)	1.567%
Expected volatility (as a percent)	45.40%
Dividend yield (as a percent)	0.00%

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Expected dividends to be paid to holders of the underlying shares or financial instruments (expressed as a percentage of the share or instrument's price).

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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Risk-free interest rate assumption used in valuing an instrument.

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Adjustment to the discount rate used to measure fair value for lack of ability to convert business interests into cash quickly.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Interest rate used to find the present value of an amount to be paid or received in the future as an input to measure fair value. For example, but not limited to, weighted average cost of capital (WACC), cost of capital, cost of equity and cost of debt.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Percentage of assumed long-term growth in revenues, used as an input to measure fair value.

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