Consolidated Statements of changes in Stockholders' Equity - USD ($)	Total	Market Offering [Member]	Common Stock [Member]	Common Stock [Member] Market Offering [Member]	Additional Paid-In Capital [Member]	Additional Paid-In Capital [Member] Market Offering [Member]	Accumulated Deficit [Member]	Accumulated Other Comprehensive Loss [Member]
Beginning Balance at Dec. 31, 2019	$ 45,520,146		$ 1,508		$ 187,914,916		$ (137,376,122)	$ (5,020,156)
Beginning Balance (in shares) at Dec. 31, 2019			15,312,167
Stock-based compensation	214,921				214,921
Vesting of restricted stock awards including withholding, net	(17,079)		$ 1		(17,080)
Vesting of restricted stock awards including withholding, net (in shares)			(5,974)
Issuance of common stock from Employee Stock Purchase Plan	56,739		$ 3		56,736
Issuance of common stock from Employee Stock Purchase Plan (in shares)			38,809
Issuance of common stock upon cashless exercise of warrants	39,974		$ 2		39,972
Issuance of common stock upon cashless exercise of warrants (in shares)			14,500
Other comprehensive income (loss) – unrealized gain (loss) on investments	(32,435)							(32,435)
Net loss	(3,885,649)						(3,885,649)
Ending Balance at Mar. 31, 2020	41,896,617		$ 1,514		188,209,465		(141,261,771)	(5,052,591)
Ending Balance (in shares) at Mar. 31, 2020			15,359,502
Beginning Balance at Dec. 31, 2020	225,876,323		$ 3,697		417,337,742		(186,420,599)	(5,044,517)
Beginning Balance (in shares) at Dec. 31, 2020			37,142,946
Stock-based compensation	1,218,351				1,218,351
Vesting of restricted stock awards including withholding, net	(92,506)		$ 1		(92,507)
Vesting of restricted stock awards including withholding, net (in shares)			(6,349)
Issuance of common stock from Employee Stock Purchase Plan	106,001		$ 1		106,000
Issuance of common stock from Employee Stock Purchase Plan (in shares)			8,733
Issuance of common stock, net		$ 34,178,231		$ 211		$ 34,178,020
Issuance of common stock, net (in shares)				2,110,800
Retirement of common stock in exchange for common stock warrant	(17,200,000)		$ (100)		(7,539,900)		(9,660,000)
Retirement of common stock in exchange for common stock warrant (in Shares)			(1,000,000)
Issuance of common stock warrant in exchange for retirement of common stock	17,200,000				17,200,000
Issuance of common stock upon cashless exercise of warrants	10,000				10,000
Issuance of common stock upon cashless exercise of warrants (in shares)			1,050
Other comprehensive income (loss) – unrealized gain (loss) on investments	5,136							5,136
Net loss	(14,864,108)						(14,864,108)
Ending Balance at Mar. 31, 2021	$ 246,437,428		$ 3,810		$ 462,417,706		$ (210,944,707)	$ (5,039,381)
Ending Balance (in shares) at Mar. 31, 2021			38,257,180