Stockholders' Equity - Stock-based Compensation Expense (Details) - USD ($)	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Stock-based compensation expense
Total stock based compensation expense	$ 177,309	$ 200,067
Options vested, fair value	34,929	188,984
Research and Development Expense
Stock-based compensation expense
Total stock based compensation expense	76,868	110,081
Selling, general and administrative expense
Stock-based compensation expense
Total stock based compensation expense	100,441	89,986
Stock Option
Stock-based compensation expense
Unrecognized compensation cost	$ 1,048,776	$ 165,954
Weighted-average remaining vesting period for recognition	2 years 1 month	9 months 19 days
Options outstanding, weighted average contractual life	8 years 9 months

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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