Consolidated Statements of Shareholders' Equity - USD ($) $ in Thousands	Total	Series B Preferred Stock [Member]	Preferred Stock [Member]	Preferred Stock [Member] Series B Preferred Stock [Member]	Common Stock [Member]	Common Stock [Member] Series B Preferred Stock [Member]	Additional Paid-in Capital [Member]	Additional Paid-in Capital [Member] Series B Preferred Stock [Member]	Accumulated Deficit [Member]	Accumulated Deficit [Member] Series B Preferred Stock [Member]
Balance at Dec. 31, 2019	$ 49,450		$ 50		$ 12		$ 188,103		$ (138,715)
Balance, shares at Dec. 31, 2019			10,000		12,446,000
Exercise of stock options	$ 5,922		$ 0		$ 1		5,921		0
Exercise of stock options, shares	358,000		0		358,000
Issuance of restricted common stock	$ 0		$ 0		$ 0		0		0
Issuance of restricted common stock, shares			0		256,000
Forfeiture of restricted common stock	0		$ 0		$ 0		0		0
Forfeiture of restricted common stock, shares			0		(15,000)
Purchase and retirement of common stock	(3,760)		$ 0		$ 0		(3,760)		0
Purchase and retirement of common stock, shares			0		(212,000)
Stock-based compensation	9,273		$ 0		$ 0		9,273		0
Net loss	(32,537)		0		0		0		(32,537)
Balance at Dec. 31, 2020	83,839		$ 50		$ 17		255,024		(171,252)
Balance, shares at Dec. 31, 2020			10,000		16,735,000
Issuance of stock, net of issuance costs	38,603	$ 16,888	$ 0	$ 17	$ 3	$ 0	38,600	$ 16,871	0	$ 0
Issuance of stock, net of issuance costs, shares			0	17,000	2,704,000
Record Series B beneficial conversion feature		11,443		$ 0		0		11,443		0
Accrete Series B beneficial conversion feature		(11,443)		0		0		(11,443)		0
Conversion of Series B preferred stock to common stock		$ 0		$ (17)		$ 1		$ 16		$ 0
Conversion of Series B preferred stock to common stock, shares				(17,000)		1,198,000
Exercise of stock options	$ 6,007		$ 0		$ 0		6,007		0
Exercise of stock options, shares	220,000		0		220,000
Issuance of restricted common stock	$ 0		$ 0		$ 0		0		0
Issuance of restricted common stock, shares			0		255,000
Vesting of restricted stock units	0		$ 0		$ 0		0		0
Vesting of restricted stock units,shares					112,000
Forfeiture of restricted common stock	0		$ 0		$ 0		0		0
Forfeiture of restricted common stock, shares			0		(65,000)
Purchase and retirement of common stock	(11,779)		$ 0		$ 0		(11,779)		0
Purchase and retirement of common stock, shares			0		(317,000)
Stock-based compensation	12,072		$ 0		$ 0		12,072		0
Net loss	(34,759)		0		0		0		(34,759)
Balance at Dec. 31, 2021	$ 55,380		$ 50		$ 17		$ 261,324		$ (206,011)
Balance, shares at Dec. 31, 2021			10,000		16,940,000
Issuance of stock, net of issuance costs, shares					0