PRINCIPAL ACCOUNTING POLICIES (Details 4)	12 Months Ended
Dec. 31, 2013 USD ($)	Dec. 31, 2013 CNY	Dec. 31, 2012 CNY	Dec. 31, 2011 CNY	Dec. 31, 2012 USD ($)	Dec. 31, 2011 USD ($)
Share based compensation
Weighted average fair value per stock option on grant date (in dollars or CNY per share)	$ 11.61	70.30	60.88	70.26
Risk-free interest rate (as a percent)	0.76%	0.76%	0.59%	1.58%
Expected life (years)	4 years	4 years	4 years	4 years
Expected dividend yield (as a percent)	0.00%	0.00%	0.00%	0.00%
Volatility (as a percent)	49.00%	49.00%	53.00%	48.00%
Fair value of the common share on date of option grant (in dollars per share)	$ 30.14				$ 23.79	$ 28.72

The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (f)(2)(iii)

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- Definition

Expected term of share-based compensation awards, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SAB TOPIC 14.D.2)

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-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 14

-Section D

-Subsection 2

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The estimated measure of the percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

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- Definition

The risk-free interest rate assumption that is used in valuing an option on its own shares.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

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- Definition

The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

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-Paragraph 2

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- Definition

Price of a single share of a number of saleable stocks of a company.

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-Topic 820

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