Available-for-Sale Securities (Tables)

9 Months Ended

Sep. 30, 2018

Investments Debt And Equity Securities [Abstract]

Summary of Available-for-sale Securities

The Company’s portfolio of available-for-sale securities consists of U.S. Treasuries and high credit quality corporate debt securities. The following is a summary of the Company’s available-for-sale securities at September 30, 2018:  

	September 30, 2018
			Gross		Gross			Fair Value
	Amortized		Unrealized		Unrealized			(Net Carrying
	Cost		Gains		Losses			Amount)
U.S. Treasury securities	$	10,002,727	$	—	$	(7,627	)	$	9,995,100
Corporate debt securities		17,619,186		—		(1,255	)		17,617,931
Total available-for-sale securities	$	27,621,913	$	—	$	(8,882	)	$	27,613,031

Summary of Contractual Maturities of Debt Investment Securities

Contractual maturities of debt investment securities at September 30, 2018 are shown below.

	Under
	1 Year		1 to 2 Years		Total
U.S. Treasury securities	$	9,995,100	$	—	$	9,995,100
Corporate debt securities		17,617,931		—		17,617,931
Total available-for-sale securities	$	27,613,031	$	—	$	27,613,031

Summary of Debt Securities with Unrealized Losses

The following table shows the gross unrealized losses and fair values of the Company’s investments that have unrealized losses, aggregated by investment category and length of time that individual securities have been in a continuous unrealized loss position as of September 30, 2018:

	Under 1 Year					1 to 2 Years				Total
			Gross					Gross				Gross
	Fair		Unrealized			Fair		Unrealized		Fair		Unrealized
	Value		Losses			Value		Losses		Value		Losses
U.S. Treasury securities	$	9,995,100	$	(7,627	)	$	—	$	—	$	9,995,100	$	(7,627	)
Corporate debt securities		2,399,726		(1,255	)		—		—		2,399,726		(1,255	)
Total available-for-sale securities with unrealized losses	$	12,394,826	$	(8,882	)	$	—	$	—	$	12,394,826	$	(8,882	)