Condensed Consolidated Statement of Changes in Stockholders' Equity (Unaudited) - 6 months ended Jun. 30, 2018 - USD ($) $ in Thousands	Common Stock [Member]	Additional Paid-In Capital [Member]	Accumulated Deficit [Member]	Total Equity Attributable to MGT Stockholders [Member]	Non-controlling Interest [Member]	Total
Balance at Dec. 31, 2017	$ 59	$ 390,736	$ (378,900)	$ 11,895	$ (22)	$ 11,873
Balance, shares at Dec. 31, 2017	58,963,009
Stock-based compensation	$ 2	2,334		2,336		2,336
Stock-based compensation, shares	2,350,000
Forfeiture of restricted stock	$ (1)	(232)		(233)		(233)
Forfeiture of restricted stock, shares	(550,000)
Stock issued for services	$ 1	1,713		1,714		1,714
Stock issued for services, shares	1,178,551
Stock issued for prior year notes payable conversion	$ 3	(3)
Stock issued for prior year notes payable conversion, shares	3,381,816
Sale of stock in connection with private placement		80		80		80
Sale of stock in connection with private placement, shares	200,000
Issuance of common stock for prior year sale	$ 1	(1)
Issuance of common stock for prior year sale, shares	750,000
Exercise of warrants	$ 6	900		906		906
Exercise of warrants, shares	5,424,250
Stock issued in disposition of cybersecurity assets		120		120		120
Stock issued in disposition of cybersecurity assets, shares	60,000
Deemed dividend		2,514	(2,514)
Warrant modification expense		139		139		139
Net loss			(11,054)	(11,054)		(11,054)
Balance at Jun. 30, 2018	$ 71	$ 398,300	$ (392,468)	$ 5,903	$ (22)	$ 5,881
Balance, shares at Jun. 30, 2018	71,757,626