v2.4.0.6

Computation of Basic Earnings per Share and Diluted Earnings Per Share (Detail) | 12 Months Ended
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Dec. 31, 2011 USD ($) | Dec. 31, 2011 CNY | Dec. 31, 2010 CNY | Dec. 31, 2009 CNY | Dec. 31, 2011 Earning Per Share, Basic USD ($) | Dec. 31, 2011 Earning Per Share, Basic CNY | Dec. 31, 2010 Earning Per Share, Basic CNY | Dec. 31, 2009 Earning Per Share, Basic CNY | Dec. 31, 2011 Earning Per Share, Diluted USD ($) | Dec. 31, 2011 Earning Per Share, Diluted CNY | Dec. 31, 2010 Earning Per Share, Diluted CNY | Dec. 31, 2009 Earning Per Share, Diluted CNY
Numerator: |  |  |  |  |  |  |  |  |  |  |  |
Net income attributable to ordinary shareholders | $ 139,812,655 | 879,966,874 | 811,187,833 | 859,313,746 | $ 139,812,655 | 879,966,874 | 811,187,833 | 859,313,746 | $ 139,812,655 | 879,966,874 | 811,187,833 | 859,313,746
Denominator: |  |  |  |  |  |  |  |  |  |  |  |
Number of shares outstanding, opening | 228,019,412 | 228,019,412 | 226,819,007 | 227,018,426 |  |  |  |  |  |  |  |
Weighted average number of shares issued | 4,104,619 | 4,104,619 | 489,847 | 726,931 |  |  |  |  |  |  |  |
Weighted average number of shares repurchased | (119,152) | (119,152) |  | (1,467,130) |  |  |  |  |  |  |  |
Weighted average number of shares outstanding - basic | 232,004,879 | 232,004,879 | 227,308,854 | 226,278,227 |  |  |  |  |  |  |  |
Dilutive effect of share options |  |  | 6,619,546 | 7,682,329 |  |  |  |  |  |  |  |
Weighted average number of shares outstanding - diluted | 232,004,879 | 232,004,879 | 233,928,400 | 233,960,556 |  |  |  |  |  |  |  |

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