Short-term Investments (Details) (USD $)	Mar. 31, 2014	Dec. 31, 2013
Schedule of Available-for-sale Securities [Line Items]
Short-term investments	$ 50,584,980	$ 27,084,980
Certificates of Deposit [Member]
Schedule of Available-for-sale Securities [Line Items]
Short-term investments	50,600,000	27,100,000
Certificates of Deposit [Member] | Maturity date of April 24, 2014 [Member]
Schedule of Available-for-sale Securities [Line Items]
Short-term investments	10,000,000
Certificates of Deposit [Member] | Maturity date of May 1, 2014 [Member]
Schedule of Available-for-sale Securities [Line Items]
Short-term investments	12,100,000
Certificates of Deposit [Member] | Maturity date of August 28, 2014 [Member]
Schedule of Available-for-sale Securities [Line Items]
Short-term investments	11,500,000
Certificates of Deposit [Member] | Maturity Date of October 30, 2014 [Member]
Schedule of Available-for-sale Securities [Line Items]
Short-term investments	5,000,000
Certificates of Deposit [Member] | Maturity Date of February 26, 2015 [Member]
Schedule of Available-for-sale Securities [Line Items]
Short-term investments	$ 12,000,000