Consolidated Statements of changes in Stockholders' Equity - USD ($)	Common Stock [Member] Market Offering [Member]	Common Stock [Member]	Additional Paid-In Capital [Member] Market Offering [Member]	Additional Paid-In Capital [Member]	Accumulated Deficit [Member]	Accumulated Other Comprehensive Loss [Member]	Market Offering [Member]	Total
Beginning Balance at Dec. 31, 2019		$ 1,508		$ 187,914,916	$ (137,376,122)	$ (5,020,156)		$ 45,520,146
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		$ 1		(17,080)				(17,079)
Vesting of restricted stock awards including withholding, net (in shares)		(5,974)
Issuance of common stock from Employee Stock Purchase Plan		$ 3		56,736				56,739
Issuance of common stock from Employee Stock Purchase Plan (in shares)		38,809
Issuance of common stock upon cashless exercise of warrants		$ 2		39,972				39,974
Issuance of common stock upon cashless exercise of warrants (in shares)		14,500
Other comprehensive (loss) income - unrealized (loss) gain on short-term investments						(32,435)		(32,435)
Net loss					(3,885,649)			(3,885,649)
Ending Balance at Mar. 31, 2020		$ 1,514		188,209,465	(141,261,771)	(5,052,591)		41,896,617
Ending Balance (in shares) at Mar. 31, 2020		15,359,502
Beginning Balance at Dec. 31, 2019		$ 1,508		187,914,916	(137,376,122)	(5,020,156)		45,520,146
Beginning Balance (in shares) at Dec. 31, 2019		15,312,167
Other comprehensive (loss) income - unrealized (loss) gain on short-term investments								(22,116)
Net loss								(38,422,700)
Ending Balance at Sep. 30, 2020		$ 3,289		380,543,640	(175,798,822)	(5,042,272)		199,705,835
Ending Balance (in shares) at Sep. 30, 2020		33,073,035
Beginning Balance at Mar. 31, 2020		$ 1,514		188,209,465	(141,261,771)	(5,052,591)		41,896,617
Beginning Balance (in shares) at Mar. 31, 2020		15,359,502
Stock-based compensation				330,510				330,510
Exercise of stock options		$ 1		36,174				36,175
Exercise of stock options (in shares)		13,935
Vesting of restricted stock awards including withholding, net		$ 1		(46,390)				(46,389)
Vesting of restricted stock awards including withholding, net (in shares)		(5,974)
Issuance of common stock in at the market offerings, net	$ 297		$ 22,780,432				$ 22,780,729
Issuance of common stock in at the market offerings, net (in shares)	2,965,144
Issuance of common stock upon cashless exercise of warrants		$ 822		31,269,341				31,270,163
Issuance of common stock upon cashless exercise of warrants (in shares)		8,221,279
Other comprehensive (loss) income - unrealized (loss) gain on short-term investments						20,888		20,888
Net loss					(16,766,916)			(16,766,916)
Ending Balance at Jun. 30, 2020		$ 2,635		242,579,532	(158,028,687)	(5,031,703)		79,521,777
Ending Balance (in shares) at Jun. 30, 2020		26,553,886
Stock-based compensation				1,320,089				1,320,089
Exercise of stock options		$ 3		90,267				90,270
Exercise of stock options (in shares)		32,189
Vesting of restricted stock awards including withholding, net		$ 13		(114,585)				(114,572)
Vesting of restricted stock awards including withholding, net (in shares)		103,551
Issuance of common stock from Employee Stock Purchase Plan		$ 5		78,727				78,732
Issuance of common stock from Employee Stock Purchase Plan (in shares)		53,852
Issuance of common stock and pre-funded warrants in public offering, net		$ 412		124,027,403				124,027,815
Issuance of common stock and pre-funded warrants in public offering, net (in shares)		4,119,564
Issuance of common stock in at the market offerings, net		$ 25		2,834,082				2,834,107
Issuance of common stock in at the market offerings, net (in shares)		247,865
Issuance of common stock upon cashless exercise of warrants		$ 196		9,728,125				9,728,321
Issuance of common stock upon cashless exercise of warrants (in shares)		1,962,128
Other comprehensive (loss) income - unrealized (loss) gain on short-term investments						(10,569)		(10,569)
Net loss					(17,770,135)			(17,770,135)
Ending Balance at Sep. 30, 2020		$ 3,289		380,543,640	(175,798,822)	(5,042,272)		199,705,835
Ending Balance (in shares) at Sep. 30, 2020		33,073,035
Beginning Balance at Dec. 31, 2020		$ 3,697		417,337,742	(186,420,599)	(5,044,517)		225,876,323
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		$ 1		(92,507)				(92,506)
Vesting of restricted stock awards including withholding, net (in shares)		(6,349)
Issuance of common stock from Employee Stock Purchase Plan		$ 1		106,000				106,001
Issuance of common stock from Employee Stock Purchase Plan (in shares)		8,733
Issuance of common stock in at the market offerings, net	$ 211		34,178,020				34,178,231
Issuance of common stock in at the market offerings, net (in shares)	2,110,800
Retirement of common stock in exchange for common stock warrant		$ (100)		(7,539,900)	(9,660,000)			(17,200,000)
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 (loss) income - unrealized (loss) gain on short-term investments						5,136		5,136
Net loss					(14,864,108)			(14,864,108)
Ending Balance at Mar. 31, 2021		$ 3,810		462,417,706	(210,944,707)	(5,039,381)		246,437,428
Ending Balance (in shares) at Mar. 31, 2021		38,257,180
Beginning Balance at Dec. 31, 2020		$ 3,697		417,337,742	(186,420,599)	(5,044,517)		225,876,323
Beginning Balance (in shares) at Dec. 31, 2020		37,142,946
Other comprehensive (loss) income - unrealized (loss) gain on short-term investments								4,354
Net loss								(73,201,503)
Ending Balance at Sep. 30, 2021		$ 3,959		483,582,367	(269,282,102)	(5,040,163)		209,264,061
Ending Balance (in shares) at Sep. 30, 2021		39,702,768
Beginning Balance at Mar. 31, 2021		$ 3,810		462,417,706	(210,944,707)	(5,039,381)		246,437,428
Beginning Balance (in shares) at Mar. 31, 2021		38,257,180
Stock-based compensation				1,484,829				1,484,829
Exercise of stock options		$ 4		94,425				94,429
Exercise of stock options (in shares)		38,217
Vesting of restricted stock awards including withholding, net		$ 1		(91,122)				(91,121)
Vesting of restricted stock awards including withholding, net (in shares)		(7,583)
Issuance of common stock in at the market offerings, net	$ 141		$ 18,177,832				$ 18,177,973
Issuance of common stock in at the market offerings, net (in shares)	1,405,710
Other comprehensive (loss) income - unrealized (loss) gain on short-term investments						1,141		1,141
Net loss					(24,826,707)			(24,826,707)
Ending Balance at Jun. 30, 2021		$ 3,956		482,083,670	(235,771,414)	(5,038,240)		241,277,972
Ending Balance (in shares) at Jun. 30, 2021		39,693,524
Stock-based compensation				1,496,884				1,496,884
Exercise of stock options				5,970				5,970
Exercise of stock options (in shares)		398
Vesting of restricted stock awards including withholding, net		$ 1		(122,626)				(122,625)
Vesting of restricted stock awards including withholding, net (in shares)		(6,521)
Issuance of common stock from Employee Stock Purchase Plan		$ 2		118,469				118,471
Issuance of common stock from Employee Stock Purchase Plan (in shares)		15,367
Other comprehensive (loss) income - unrealized (loss) gain on short-term investments						(1,923)		(1,923)
Net loss					(33,510,688)			(33,510,688)
Ending Balance at Sep. 30, 2021		$ 3,959		$ 483,582,367	$ (269,282,102)	$ (5,040,163)		$ 209,264,061
Ending Balance (in shares) at Sep. 30, 2021		39,702,768