Investment (Detail) (USD $)	Dec. 31, 2012	Dec. 31, 2011
Schedule of Held-to-maturity Securities [Line Items]
- Current	$ 49,035,610	$ 20,714,145
- Non-current		1,892,308
Other long-term investments	3,106,692
Total	$ 52,142,302	$ 22,606,453

This item represents the aggregate carrying amount of all cost-method investments as reported on or included in the balance sheet. The original cost of the investments may differ from the aggregate carrying amount disclosed due to various adjustments such as: (i) dividends received in excess of earnings after the date of investment that are considered a return of investment and therefore recorded as reductions to cost of the investment, or (ii) a series of operating losses of an investee or other factors which may indicate that a decrease in value of the investment has occurred which is other than temporary and accordingly such decrease in value has been recognized.

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- Definition

For an unclassified balance sheet, this item represents investments in debt securities which are categorized as held-to-maturity. The held-to-maturity category is for those securities that the entity has the positive intent and ability to hold until maturity.

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This item represents investments in debt securities which are categorized as held-to-maturity and that have scheduled maturities within one year of the balance sheet date or the normal operating cycle, whichever is longer; such investments are measured at amortized cost (carrying value). The held-to-maturity category is for those securities that the Entity has the positive intent and ability to hold until maturity.

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+ Details

- Definition

This item represents investments in debt securities which are categorized as held-to-maturity and that have scheduled maturities more than one year from the balance sheet date or operating cycle, if longer; such investments are measured at amortized cost (carrying value). The held-to-maturity category is for those securities that the Entity has the positive intent and ability to hold until maturity.

+ References+ Details