Fair Value of Financial Instruments (Tables)

9 Months Ended

Sep. 30, 2014

Fair Value Disclosures [Abstract]

Assets Measured or Disclosed at Fair Value on Recurring Basis

Assets measured or disclosed at fair value on a recurring basis as of September 30, 2014 are summarized below:

	Fair Value Measurements Using
	Level 1		Level 2		Level 3		Total
Assets:
Cash and cash equivalents	$	49,667,984	$	—	$	—	$	49,667,984
Certificates of deposit		—		10,014,977		—	$	10,014,977
U.S. Government debt securities		—		31,718,959		—	$	31,718,959
Commercial paper		—		4,997,360		—	$	4,997,360
Corporate debt securities		—		21,938,973		—	$	21,938,973
	$	49,667,984	$	68,670,269	$	—	$	118,338,253

Assets measured or disclosed at fair value on a recurring basis as of December 31, 2013 are summarized below:

	Fair Value Measurements Using
	Level 1		Level 2		Level 3		Total
Assets:
Cash and cash equivalents	$	21,215,228	$	—	$	—	$	21,215,228
Certificates of deposit		—		1,330,132		—		1,330,132
U.S. Government debt securities		—		7,509,369		—		7,509,369
Corporate debt securities		—		2,501,740		—		2,501,740
	$	21,215,228	$	11,341,241	$	—	$	32,556,469