CONDENSED CONSOLIDATED STATEMENTS OF STOCKHOLDERS' DEFICIT - USD ($)	Total	Revision of Prior Period, Adjustment	Common Stock Issued	Common Stock Issued Revision of Prior Period, Adjustment	Additional Paid-in Capital	Additional Paid-in Capital Revision of Prior Period, Adjustment	Treasury Stock	Treasury Stock Revision of Prior Period, Adjustment	Accumulated Deficit
Balance beginning of period (in shares) at Dec. 31, 2019			112,703,926				1,885,277
Balance, beginning of period at Dec. 31, 2019	$ 34,398,000		$ 113,000		$ 147,231,000		$ (10,806,000)		$ (102,140,000)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Share-based compensation expense	3,781,000				3,781,000
Exercise of stock options	298,000				(1,658,000)		$ 1,956,000
Exercise of stock options (in shares)							(220,300)
Issuance of restricted stock	0				0		$ 0
Issuance of restricted stock (in shares)							0
Restricted stock canceled/forfeited	0				2,124,000		$ (2,124,000)
Restricted stock canceled/forfeited (in shares)							285,611
Shares repurchased for tax withholding (in shares)							461,934
Shares repurchased for tax withholding	(2,330,000)				147,000		$ (2,477,000)
Net loss	(13,287,000)								(13,287,000)
Balance end of period (in shares) at Jun. 30, 2020			112,703,926				2,412,522
Balance, end of period at Jun. 30, 2020	22,860,000		$ 113,000		151,625,000		$ (13,451,000)		(115,427,000)
Balance beginning of period (in shares) at Mar. 31, 2020			112,703,926				2,163,066
Balance, beginning of period at Mar. 31, 2020	30,339,000		$ 113,000		149,765,000		$ (12,578,000)		(106,961,000)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Share-based compensation expense	1,866,000				1,866,000
Exercise of stock options	0				(444,000)		$ 444,000
Exercise of stock options (in shares)							(50,000)
Restricted stock canceled/forfeited	0				378,000		$ (378,000)
Restricted stock canceled/forfeited (in shares)							42,613
Shares repurchased for tax withholding (in shares)							256,843
Shares repurchased for tax withholding	(879,000)				60,000		$ (939,000)
Net loss	(8,466,000)								(8,466,000)
Balance end of period (in shares) at Jun. 30, 2020			112,703,926				2,412,522
Balance, end of period at Jun. 30, 2020	$ 22,860,000		$ 113,000		151,625,000		$ (13,451,000)		(115,427,000)
Balance beginning of period (in shares) at Dec. 31, 2020	112,703,926		112,703,926				1,773,683
Balance, beginning of period at Dec. 31, 2020	$ (150,000)		$ 113,000		158,610,000		$ (7,449,000)		(151,424,000)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Correction of out-of-period error (Note 1) | Stock Award Misstatements		$ 0				$ (2,009,000)		$ 2,009,000
Correction of out-of-period error (Note 1) (in shares) | Stock Award Misstatements				239,502				(239,502)
Deemed dividends	(926,000)				(926,000)
Share-based compensation expense	7,304,000				7,304,000
Exercise of stock options	$ 1,359,000				(934,000)		$ 2,293,000
Exercise of stock options (in shares)	(494,139)						(452,329)
Issuance of restricted stock	$ 0				(3,576,000)		$ 3,576,000
Issuance of restricted stock (in shares)							(761,775)
Restricted stock canceled/forfeited	0				251,000		$ (251,000)
Restricted stock canceled/forfeited (in shares)							48,026
Shares repurchased for tax withholding (in shares)							453,885
Shares repurchased for tax withholding	(4,563,000)						$ (4,563,000)
Net loss	$ (10,161,000)								(10,161,000)
Balance end of period (in shares) at Jun. 30, 2021	112,703,926		112,703,926				821,988
Balance, end of period at Jun. 30, 2021	$ (7,137,000)		$ 113,000		158,720,000		$ (4,385,000)		(161,585,000)
Balance beginning of period (in shares) at Mar. 31, 2021			112,703,926				1,083,297
Balance, beginning of period at Mar. 31, 2021	(8,051,000)		$ 113,000		156,733,000		$ (5,091,000)		(159,806,000)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Correction of out-of-period error (Note 1) | Stock Award Misstatements		$ 0				$ (928,000)		$ 928,000
Correction of out-of-period error (Note 1) (in shares) | Stock Award Misstatements								(239,502)
Deemed dividends	(464,000)				(464,000)
Share-based compensation expense	4,060,000				4,060,000
Exercise of stock options	444,000				(668,000)		$ 1,112,000
Exercise of stock options (in shares)							(141,516)
Issuance of restricted stock	0				(116,000)		$ 116,000
Issuance of restricted stock (in shares)							(19,774)
Restricted stock canceled/forfeited	0				103,000		$ (103,000)
Restricted stock canceled/forfeited (in shares)							12,437
Shares repurchased for tax withholding (in shares)							127,046
Shares repurchased for tax withholding	(1,347,000)						$ (1,347,000)
Net loss	$ (1,779,000)								(1,779,000)
Balance end of period (in shares) at Jun. 30, 2021	112,703,926		112,703,926				821,988
Balance, end of period at Jun. 30, 2021	$ (7,137,000)		$ 113,000		$ 158,720,000		$ (4,385,000)		$ (161,585,000)