CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY - USD ($) $ in Thousands	Common Stock	Additional Paid-In Capital	Treasury Stock	Accumulated Other Comprehensive Loss	Accumulated Deficit	Total
Balance, beginning (in shares) (in thousands) at Dec. 31, 2019	19,053,854
Balance, beginning at Dec. 31, 2019	$ 2	$ 250,092	$ (5,297)	$ (2,380)	$ (209,250)	$ 33,167
Net income (loss)					364	364
Other comprehensive income (loss)				(212)		(212)
Issuance of common stock upon exercise of stock options & RSU releases (in shares) (in thousands)	0
Issuance of common stock under employee stock purchase plan (in shares) (in thousands)	0
Stock-based compensation expense		114				114
Balance, ending (in shares) (in thousands) at Mar. 31, 2020	19,053,854
Balance, ending at Mar. 31, 2020	$ 2	250,206	(5,297)	(2,592)	(208,886)	33,433
Balance, beginning (in shares) (in thousands) at Dec. 31, 2020	19,490
Balance, beginning at Dec. 31, 2020	$ 2	250,954	(5,297)	(2,419)	(208,804)	34,436
Net income (loss)					(1,994)	(1,994)
Other comprehensive income (loss)				(5)		(5)
Issuance of common stock upon exercise of stock options & RSU releases (in shares) (in thousands)	689
Issuance of common stock upon exercise of stock options & RSU releases	$ 0	997				997
Issuance of common stock per Greenidge Merger Agreement, shares	3,910
Issuance of common stock per Greenidge Merger Agreement,	$ 1	7,233				7,234
Issuance of common stock under employee stock purchase plan (in shares) (in thousands)	0
Stock-based compensation expense		217				217
Balance, ending (in shares) (in thousands) at Mar. 31, 2021	24,089
Balance, ending at Mar. 31, 2021	$ 3	$ 259,401	$ (5,297)	$ (2,424)	$ (210,799)	$ 40,885