Summary of Significant Accounting Policies (Tables)

12 Months Ended

Dec. 31, 2020

Accounting Policies [Abstract]

Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions

	Expected Volatility	Risk-free Interest Rate	Expected Term	Dividend Rate
December 31, 2020:
Employees	98%	1.3%	4	0	%
Officers and non-employee directors	85%	1.4%	7	0	%
December 31, 2019:
Employees	88%	2.2%	4	0	%
Officers and non-employee directors	77%	2.6%	8	0	%
December 31, 2018:
Employees	58%	2.6%	4	0	%
Officers and non-employee directors	63%	2.8%	8	0	%