v2.4.0.6

Treasury Stock - Additional Information (Detail) |  |  |  |  | 12 Months Ended
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Dec. 31, 2011 USD ($) | Dec. 31, 2011 CNY | Dec. 31, 2010 CNY | Dec. 31, 2011 Stock Repurchase Plan American Depositary Share USD ($) | Dec. 31, 2011 Stock Repurchase Plan American Depositary Share CNY | Dec. 31, 2010 Stock Repurchase Plan American Depositary Share CNY | Dec. 31, 2011 Share Options American Depositary Share | Dec. 31, 2011 Stock Repurchase Plan 4 American Depositary Share USD ($) | Dec. 31, 2011 Stock Repurchase Plan 4 American Depositary Share CNY
Share Repurchases [Line Items] |  |  |  |  |  |  |  |  |
Treasury Stock Shares |  |  |  |  |  |  |  | 932,972 | 932,972
Treasury Stock Value | $ 337,235,151 | 2,122,524,316 | 2,176,792,033 | $ 350,000,000 | 2,200,000,000 | 2,177,000,000 |  | $ 3,648,097 | 22,960,759
Treasury Stock Shares |  |  |  | 34,935,057 | 34,935,057 | 34,002,085 |  |  |
Number of share used to settle the exercise of share options |  |  |  |  |  |  | 1,314,272 |  |

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- Definition Number of treasury shares (units) reissued during the period, excluding reissuance of shares (units) held in treasury used to satisfy equity-based compensation obligations exercised by the holders of such rights. Upon reissuance of shares (units) from treasury, either the common or preferred stock (unit) reissued is outstanding. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Principles Board Opinion (APB) -Number 12 -Paragraph 10 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Article 3 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21463-112644 + Details
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- Definition Number of common and preferred shares that were previously issued and that were repurchased by the issuing entity and held in treasury on the financial statement date. This stock has no voting rights and receives no dividends. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 29, 30 -Article 5 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.28,29) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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- Definition Number of shares that have been repurchased during the period and are being held in treasury. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21463-112644 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Principles Board Opinion (APB) -Number 12 -Paragraph 10 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Article 3 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 29, 30 -Article 5 + Details
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- Definition The amount allocated to treasury stock. Treasury stock is common and preferred shares of an entity that were issued, repurchased by the entity, and are held in its treasury. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name FASB Technical Bulletin (FTB) -Number 85-6 -Paragraph 3 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 30 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=6405834&loc=d3e23315-112656 + Details
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