Organization and Basis of Presentation (Details Narrative) - USD ($) $ in Thousands					3 Months Ended			6 Months Ended		12 Months Ended
	Jun. 13, 2018	Mar. 23, 2018	Mar. 19, 2018	Mar. 16, 2018	Jun. 30, 2018	Mar. 31, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017	Dec. 31, 2017	May 16, 2018
Organization, Consolidation and Presentation of Financial Statements Disclosure [Line Items]
Common stock, shares authorized		75,000,000			125,000,000			125,000,000		125,000,000
Common stock reverse split		The Company's stockholders approved a 1-for-2 reverse split of the Company's common stock, to be effected only if needed for the Company's application to uplist its common stock to a national exchange.
Universal shelf registration statement amount	$ 150,000
Description on Cryptocurrency mining						The Company took delivery of an additional 2,000 Bitcoin mining machines in Sweden and moved 4,300 machines (including 2,100 investor-owned machines) from Washington to Sweden.		The Company mined 145.8 Bitcoin
Customer deposits											$ 368
Facility expense					$ 2,499			$ 2,499
Revenue on mining								1,355
Sale of asset in consideration			$ 60	$ 60				$ 60
Percentage of convertible into equity interest			20.00%
Promissory Note [Member]
Organization, Consolidation and Presentation of Financial Statements Disclosure [Line Items]
Sale of asset in consideration			$ 1,000	$ 1,000
Percentage of convertible into equity interest				20.00%
Quincy [Member]
Organization, Consolidation and Presentation of Financial Statements Disclosure [Line Items]
Description on Cryptocurrency mining								MGT owned and operated approximately 500 miners located in a leased facility in Quincy, Washington and 4,200 miners located in a leased facility in Sweden. In addition, the Company operates about 2,100 miners in the Sweden location pursuant to management agreements. All miners owned or managed by MGT are S9 Antminers sold by Bitmain Technologies LTD. In addition to the S9 Antminers, the Company owns 50 custom designed GPU-based Ethereum mining rigs.
Vendors [Member]
Organization, Consolidation and Presentation of Financial Statements Disclosure [Line Items]
Facility expense					1,350
Service Providers [Member]
Organization, Consolidation and Presentation of Financial Statements Disclosure [Line Items]
Facility expense					$ 1,149
Hosting Agreement [Member] | Beacon Leasing LLC [Member]
Organization, Consolidation and Presentation of Financial Statements Disclosure [Line Items]
Fixed price of electricity capacity per month										$ 810
Paid to electricity charges first and last month of services										$ 1,620