Fair Value Instruments - Financial Assets and Liabilities Measured at Fair Value on Recurring Basis (Details) - Fair Value, Measurements, Recurring - USD ($)	Sep. 30, 2017	Dec. 31, 2016
Asset included in:
Financial Assets	$ 8,369,374	$ 10,748,003
Cash and Cash Equivalents | Money Market Securities
Asset included in:
Financial Assets	8,369,374	6,443,102
Investments Available-for-sale at Fair Value | U.S. Government Obligations
Asset included in:
Financial Assets		1,300,663
Investments Available-for-sale at Fair Value | Corporate Debt Securities
Asset included in:
Financial Assets		3,004,238
Level 1
Asset included in:
Financial Assets	8,369,374	7,743,765
Level 1 | Cash and Cash Equivalents | Money Market Securities
Asset included in:
Financial Assets	$ 8,369,374	6,443,102
Level 1 | Investments Available-for-sale at Fair Value | U.S. Government Obligations
Asset included in:
Financial Assets		1,300,663
Level 2
Asset included in:
Financial Assets		3,004,238
Level 2 | Investments Available-for-sale at Fair Value | Corporate Debt Securities
Asset included in:
Financial Assets		$ 3,004,238