Condensed Consolidated Statements of Shareholders' Equity - USD ($) $ in Thousands	Total	Common Stock	Treasury Stock	Additional Paid-in Capital	Accumulated Other Comprehensive Income (Loss)	Accumulated Deficit
Increase (Decrease) in Stockholders' Equity
Treasury stock (in shares) beginning balance			0
Balances (in shares) at Dec. 31, 2022		208,150,021
Balances at Dec. 31, 2022	$ 126,259	$ 0	$ 0	$ 1,998,314	$ (3,488)	$ (1,868,567)
Increase (Decrease) in Stockholders' Equity
Stock-based compensation expense	3,131			3,131
Shares issued upon vesting of restricted stock units and for exercises of stock options (in shares)		(697,815)
Shares issued upon vesting of restricted stock units	0
Shares issued for accrued compensation (in shares)		2,206,469
Shares issued for accrued compensation	3,361			3,361
Shares issued as payment for services (in shares)		(465,808)
Shares issued as payment for services	545			545
Shares issued in public offering, net of issuance costs (in shares)		43,962,640
Shares issued in public offerings, net of issuance costs	72,782			72,782
Net loss	(22,734)					(22,734)
Other comprehensive loss	789				789
Treasury stock (in shares) ending balance at Mar. 31, 2023			0
Balances (in shares) at Mar. 31, 2023		255,482,753
Balances at Mar. 31, 2023	$ 184,133	$ 0	$ 0	2,078,133	(2,699)	(1,891,301)
Increase (Decrease) in Stockholders' Equity
Treasury stock (in shares) beginning balance			0
Treasury stock (in shares) beginning balance			7,479,431
Balances (in shares) at Dec. 31, 2023	248,919,096	248,919,096
Balances at Dec. 31, 2023	$ 118,498	$ 0	$ 0	2,084,916	(1,947)	(1,964,471)
Increase (Decrease) in Stockholders' Equity
Stock-based compensation expense	2,581			2,581
Shares issued upon vesting of restricted stock units and for exercises of stock options (in shares)		(961,534)	(961,534)
Shares issued upon vesting of restricted stock units	0
Shares issued as payment for services (in shares)		(368,178)	(368,178)
Shares issued as payment for services	528			528
Net loss	(23,738)					(23,738)
Other comprehensive loss	$ (850)				(850)
Treasury stock (in shares) ending balance at Mar. 31, 2024			6,149,719
Balances (in shares) at Mar. 31, 2024	250,248,808	250,248,808
Balances at Mar. 31, 2024	$ 97,019	$ 0	$ 0	$ 2,088,025	$ (2,797)	$ (1,988,209)
Increase (Decrease) in Stockholders' Equity
Treasury stock (in shares) beginning balance			6,149,719