INVESTMENTS - Long-term investments - Additional information (Detail) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2011 USD ($)	Dec. 31, 2011 CNY	Dec. 31, 2010 CNY	Dec. 31, 2009 CNY
Schedule of Investments [Line Items]
Impairment charges on long-term investments	$ 7.61	47.89	0	0

The amount by which the fair value of an investment is less than the amortized cost basis or carrying amount of that investment at the balance sheet date and the decline in fair value is deemed to be other than temporary, before considering whether or not such amount is recognized in earnings or other comprehensive income.

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