Cash, Cash Equivalents and Short-Term Investments

3 Months Ended

Mar. 31, 2018

Cash Cash Equivalents And Available For Sale Securities [Abstract]

INVESTMENTS

3. INVESTMENTS

The Company invests its excess cash in fixed income instruments denominated and payable in U.S. dollars including, U.S. treasury securities, commercial paper, corporate debt securities and assets-backed securities in accordance with the Company’s investment policy that primarily seeks to maintain adequate liquidity and preserve capital.

The Company has designated all investments as available-for-sale and therefore such investments are reported at fair value. Unrealized gains or losses on investments are recorded in accumulated other comprehensive income or loss, a component of stockholders’ deficit, on the Company’s condensed consolidated balance sheets.

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

March 31, 2018	Amortized Cost		Unrealized Gains		Unrealized Loss			Fair Value
Cash equivalents and short-term investments
Money market funds	$	28,831,110	$	—	$	—		$	28,831,110
Asset-backed securities		8,099,245		—		(8,721	)		8,090,524
Commercial paper		32,277,246		—		—			32,277,246
Corporate debt securities		21,433,498		—		(53,474	)		21,380,024
U.S. Treasury securities		24,916,290		—		(23,970	)		24,892,320
Total	$	115,557,389	$	—	$	(86,165	)	$	115,471,224
December 31, 2017	Amortized Cost		Unrealized Gains		Unrealized Loss			Fair Value
Cash equivalents and short-term investments
Money market 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

As of March 31, 2018, the Company does not consider those securities that are in an unrealized loss position to be other-than-temporarily impaired, as it has the ability to hold such investments until recovery of the fair value. The Company utilizes the specific identification method in computing realized gains and losses. The Company had no realized gains and losses on its available-for-sale securities for the three months ended March 31, 2018 and year ended December 31, 2017. The contractual maturity dates of all of the Company’s investments are less than one year.