Short-term Investments (Details) - USD ($)	Sep. 30, 2015	Dec. 31, 2014
Schedule of Available-for-sale Securities [Line Items]
Short-term investments	$ 15,022,454	$ 45,621,593
Certificates of Deposit [Member] | Maturing on November 27, 2015 [Member]
Schedule of Available-for-sale Securities [Line Items]
Short-term investments	3,000,000
Certificates of Deposit [Member] | Maturing on February 25, 2016 [Member]
Schedule of Available-for-sale Securities [Line Items]
Short-term investments	$ 12,000,000