Prepayments and Other Current Assets (Details)	Dec. 31, 2014 USD ($)	Dec. 31, 2014 CNY	Dec. 31, 2013 CNY
Prepayments and Other Current Assets
Prepayments to suppliers	$ 80,311,076us-gaap_Supplies	498,298,101us-gaap_Supplies	274,418,870us-gaap_Supplies
Interest income receivable	1,049,199us-gaap_InterestReceivableCurrent	6,509,860us-gaap_InterestReceivableCurrent	3,767,451us-gaap_InterestReceivableCurrent
Prepayment for advertising expenses	8,649,132us-gaap_PrepaidAdvertising	53,664,403us-gaap_PrepaidAdvertising	3,007,874us-gaap_PrepaidAdvertising
Others	2,711,624us-gaap_OtherAssetsCurrent	16,824,542us-gaap_OtherAssetsCurrent	5,366,052us-gaap_OtherAssetsCurrent
Total	$ 92,721,031	575,296,906	286,560,247

Carrying amount as of the balance sheet date of current interest earned but not received. Also called accrued interest or accrued interest receivable. For classified balance sheets, represents the current amount receivable, that is amounts expected to be collected within one year or the normal operating cycle, if longer.

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Aggregate carrying amount, as of the balance sheet date, of current assets not separately disclosed in the balance sheet. Current assets are expected to be realized or consumed within one year (or the normal operating cycle, if longer).

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Amount of consideration paid in advance for advertising that provides economic benefits within a future period of one year or the normal operating cycle, if longer.

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Amount of asset related to consideration paid in advance for costs that provide economic benefits in future periods, and amount of other assets that are expected to be realized or consumed within one year or the normal operating cycle, if longer.

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Amount of consideration paid in advance for supplies that provide economic benefits within a future period of one year or the normal operating cycle, if longer.

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