Marketable Securities

6 Months Ended

Jun. 30, 2017

Investments Debt And Equity Securities [Abstract]

Marketable Securities

4. Marketable Securities

The Company invests its excess cash in money market funds and debt instruments of financial institutions, corporations, government sponsored entities and municipalities. The following tables summarize the Company’s marketable securities:

As of June 30, 2017	Maturity (in years)	Amortized Cost		Unrealized Gains		Unrealized Losses			Estimated Fair Value
Corporate debt securities	1 or less	$	72,455,706	$	1,823	$	(24,461	)	$	72,433,068
Total		$	72,455,706	$	1,823	$	(24,461	)	$	72,433,068

As of December 31, 2016	Maturity (in years)	Amortized Cost		Unrealized Gains		Unrealized Losses			Estimated Fair Value
Corporate debt securities	1 or less	$	18,937,860	$	901	$	(7,046	)	$	18,931,715
Total		$	18,937,860	$	901	$	(7,046	)	$	18,931,715