Movement in Allowance for Doubtful Accounts (Detail) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2012 USD ($)	Dec. 31, 2012 CNY	Dec. 31, 2011 CNY	Dec. 31, 2010 CNY
Financing Receivable, Allowance for Credit Losses [Line Items]
Balance as of January 1	$ 932	5,806	2,223	9,015
Amounts (credited against) charged to costs and expenses	(6)	(38)	3,583	(6,792)
Balance as of December 31	$ 926	5,768	5,806	2,223

Total of allowances and reserves, the valuation and qualifying accounts that are either netted against the cost of an asset (in order to value it at its carrying value) or that reflect a liability established to represent expected future costs, charged to costs and expenses.

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 09

-Article 12

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

-Section S99

-Paragraph 4

-URI http://asc.fasb.org/extlink&oid=6881521&loc=d3e24092-122690

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration