Investments (Tables)

12 Months Ended

Dec. 31, 2015

Investments

Schedule of cash, cash equivalents and investments

			Gross		Gross
	Amortized		Unrealized		Unrealized		Fair
	Cost		Gains		Losses		Value
December 31, 2014
Cash and cash equivalents:
Cash and money market accounts	$	13,073,137		—		—	$	13,073,137
Total cash and cash equivalents	$	13,073,137	$	—	$	—	$	13,073,137
Short-term investments:
Corporate bonds	$	37,136,494		—	$	(11,908)	$	37,124,586
Commercial paper		3,495,972		3,791		—		3,499,763
Total short-term investments	$	40,632,466	$	3,791	$	(11,908)	$	40,624,349
Total cash, cash equivalents, and investments	$	53,705,603	$	3,791	$	(11,908)	$	53,697,486
December 31, 2015
Cash and cash equivalents:
Cash and money market accounts	$	15,302,382		—		—	$	15,302,382
Total cash and cash equivalents	$	15,302,382	$	—	$	—	$	15,302,382
Short-term investments:
Corporate bonds	$	3,108,516		—	$	(1,069)	$	3,107,447
Commercial paper		1,999,082		98		—		1,999,180
Total short-term investments	$	5,107,598	$	98	$	(1,069)	$	5,106,627
Total cash, cash equivalents, and investments	$	20,409,980	$	98	$	(1,069)	$	20,409,009