Condensed Consolidated Statements of Stockholders' Equity (Unaudited) - USD ($) shares in Thousands	Common Stock Outstanding [Member]	Additional Paid-in Capital [Member]	AOCI Attributable to Parent [Member]	Retained Earnings [Member]	Total
Balance (in shares) at Dec. 31, 2021	100,832
Balance at Dec. 31, 2021	$ 10,000	$ 373,657,000	$ 0	$ (233,589,000)	$ 140,078,000
Vesting of share-based awards (in shares)	73
Vesting of share-based awards	$ 0	0	0	0	0
Stock-based compensation	0	1,574,000	0	0	1,574,000
Net loss	0	0	0	(7,162,000)	(7,162,000)
Stock-based compensation	$ 0	1,574,000	0	0	1,574,000
Balance (in shares) at Mar. 31, 2022	100,905
Balance at Mar. 31, 2022	$ 10,000	375,231,000	0	(240,751,000)	134,490,000
Balance (in shares) at Dec. 31, 2021	100,832
Balance at Dec. 31, 2021	$ 10,000	373,657,000	0	(233,589,000)	140,078,000
Unrealized gain (loss) on marketable securities					(641,000)
Net loss					(27,631,000)
Balance (in shares) at Sep. 30, 2022	101,032
Balance at Sep. 30, 2022	$ 10,000	377,967,000	(641,000)	(261,220,000)	116,116,000
Balance (in shares) at Mar. 31, 2022	100,905
Balance at Mar. 31, 2022	$ 10,000	375,231,000	0	(240,751,000)	134,490,000
Vesting of share-based awards (in shares)	63
Vesting of share-based awards	$ 0	0	0	0	0
Stock-based compensation	0	1,444,000	0	0	1,444,000
Unrealized gain (loss) on marketable securities	0	0	(512,000)	0	(512,000)
Net loss	0	0	0	(8,494)	(8,494,000)
Stock-based compensation	$ 0	1,444,000	0	0	1,444,000
Balance (in shares) at Jun. 30, 2022	100,968
Balance at Jun. 30, 2022	$ 10,000	376,675,000	(512,000)	(249,245,000)	126,928,000
Vesting of share-based awards (in shares)	62
Vesting of share-based awards	$ 0	0	0	0	0
Stock-based compensation	$ 0	1,287,000	0	0	1,287,000
Common stock issued upon exercise of options (in shares)	2
Common stock issued upon exercise of options	$ 0	5,000	0	0	5,000
Unrealized gain (loss) on marketable securities	0	0	(129,000)	0	(129,000)
Net loss	0	0	0	(11,975,000)	(11,975,000)
Stock-based compensation	$ 0	1,287,000	0	0	1,287,000
Balance (in shares) at Sep. 30, 2022	101,032
Balance at Sep. 30, 2022	$ 10,000	377,967,000	(641,000)	(261,220,000)	116,116,000
Balance (in shares) at Dec. 31, 2022	126,302
Balance at Dec. 31, 2022	$ 13,000	454,741,000	(302,000)	(272,814,000)	181,638,000
Vesting of share-based awards (in shares)	61
Vesting of share-based awards	$ 0	0	0	0	0
Stock-based compensation	$ 0	1,267,000	0	0	1,267,000
Common stock issued upon exercise of options (in shares)	12
Common stock issued upon exercise of options	$ 0	41,000	0	0	41,000
Unrealized gain (loss) on marketable securities	0	0	156,000	0	156,000
Net loss	0	0	0	(7,837,000)	(7,837,000)
Stock-based compensation	$ 0	1,267,000	0	0	1,267,000
Balance (in shares) at Mar. 31, 2023	126,375
Balance at Mar. 31, 2023	$ 13,000	456,049,000	(146,000)	(280,651,000)	175,265,000
Balance (in shares) at Dec. 31, 2022	126,302
Balance at Dec. 31, 2022	$ 13,000	454,741,000	(302,000)	(272,814,000)	$ 181,638,000
Common stock issued upon exercise of options (in shares)					29
Unrealized gain (loss) on marketable securities					$ (128,000)
Net loss					(29,079,000)
Balance (in shares) at Sep. 30, 2023	127,445
Balance at Sep. 30, 2023	$ 13,000	462,355,000	(430,000)	(301,893,000)	160,045,000
Balance (in shares) at Mar. 31, 2023	126,375
Balance at Mar. 31, 2023	$ 13,000	456,049,000	(146,000)	(280,651,000)	175,265,000
Vesting of share-based awards (in shares)	61
Vesting of share-based awards	$ 0	0	0	0	0
Stock-based compensation	0	1,628,000	0	0	1,628,000
Unrealized gain (loss) on marketable securities	0	0	(361,000)	0	(361,000)
Net loss	$ 0	0	0	(11,278,000)	(11,278,000)
Common shares issued, net of issuance costs of $0.1 million (in shares)	952
Common shares issued, net of issuance costs of $0.1 million	$ 0	3,032,000	0	0	3,032,000
Stock-based compensation	$ 0	1,628,000	0	0	1,628,000
Balance (in shares) at Jun. 30, 2023	127,388
Balance at Jun. 30, 2023	$ 13,000	460,709,000	(507,000)	(291,929,000)	168,286,000
Vesting of share-based awards (in shares)	41
Vesting of share-based awards	$ 0	0	0	0	0
Stock-based compensation	$ 0	1,625,000	0	0	1,625,000
Common stock issued upon exercise of options (in shares)	16
Common stock issued upon exercise of options	$ 0	21,000	0	0	21,000
Unrealized gain (loss) on marketable securities	0	0	77,000	0	77,000
Net loss	0	0	0	(9,964,000)	(9,964,000)
Stock-based compensation	$ 0	1,625,000	0	0	1,625,000
Balance (in shares) at Sep. 30, 2023	127,445
Balance at Sep. 30, 2023	$ 13,000	$ 462,355,000	$ (430,000)	$ (301,893,000)	$ 160,045,000