Investments (Tables)

9 Months Ended

Sep. 30, 2018

Investments Disclosure [Abstract]

Summary of Investments Included in Cash Equivalents and Short Term Investments

The following table summarizes the Company’s investments, which are included in cash equivalents and short-term investments, as of September 30, 2018 and December 31, 2017:

As of September 30, 2018	Amortized Cost		Unrealized Gains		Unrealized Losses			Fair Value
Money market mutual funds	$	11,441,399	$	—	$	—		$	11,441,399
Asset-backed securities		19,485,610		367		(3,543	)		19,482,434
Commercial paper		98,181,285		—		—			98,181,285
Corporate debt securities		54,428,208		6,772		(11,505	)		54,423,475
U.S. Treasury securities		54,440,052		—		(12,969	)		54,427,083
Total	$	237,976,554	$	7,139	$	(28,017	)	$	237,955,676
As of December 31, 2017	Amortized Cost		Unrealized Gains		Unrealized Losses			Fair Value
Money market mutual funds	$	44,181,756	$	—	$	—		$	44,181,756
Asset-backed securities		7,428,021		—		(6,318	)		7,421,703
Commercial paper		34,882,298		—		—			34,882,298
Corporate debt securities		26,905,815		—		(49,532	)		26,856,283
U.S. Treasury securities		8,940,778		—		(17,458	)		8,923,320
Total	$	122,338,668	$	—	$	(73,308	)	$	122,265,360