Net Loss Per Share (Schedule of Excluded Potential Common Shares from Computation of Diluted Net Loss Per Share) (Details) - shares	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Excluded potential common shares from computation of diluted net loss per share	22,502,097	19,841,206
Options issued and outstanding [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Excluded potential common shares from computation of diluted net loss per share	20,574,077	19,712,504
Warrants issued and outstanding [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Excluded potential common shares from computation of diluted net loss per share	1,928,020	128,702