Subsequent events (Details Textual) - Subsequent Event [Member] - Exchange Agreement [Member] $ in Thousands	Mar. 24, 2016 USD ($) shares
Notes Payable	$ 1,875
Interest Expense, Debt	$ 51
Debt Instrument, Convertible, Terms of Conversion Feature	The Preferred Shares are convertible into an aggregate of 366,630 shares of DraftDay's common stock, except that conversions shall not be effected to the extent that, after issuance of the conversion shares, MGT's aggregate beneficial ownership (together with that of its affiliates) would exceed 9.99%.
Debt Instrument, Debt Default, Amount	$ 940
Debt Instrument, Interest Rate, Stated Percentage	5.00%
Debt Instrument, Maturity Date	Jul. 31, 2016
Common Stock [Member]
Debt Conversion, Converted Instrument, Amount	$ 825
Debt Conversion, Converted Instrument, Shares Issued \| shares	2,748,353
Preferred Stock [Member]
Debt Conversion, Converted Instrument, Amount	$ 110
Debt Conversion, Converted Instrument, Shares Issued \| shares	110

The value of the financial instrument(s) that the original debt is being converted into in a noncash (or part noncash) transaction. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period.

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The number of shares issued in exchange for the original debt being converted in a noncash (or part noncash) transaction. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or payments in the period.

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Amount of outstanding long-term debt or borrowing associated with any securities or credit agreement for which there has been a default in principal, interest, sinking fund, or redemption provisions, or any breach of covenant that existed at the end of the period and subsequently has not been cured.

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Description of the conversion terms of a debt instrument which may include the conversion ratio (including all potential conversion ratios if contingently adjustable), type of debt or equity security into which the debt is convertible, the dollars of debt or the number of shares into which the instrument is convertible (or potentially convertible into), the conversion period, any contingencies associated with the conversion terms, and the existence and amount of a beneficial conversion feature.

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Contractual interest rate for funds borrowed, under the debt agreement.

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Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

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Amount of the cost of borrowed funds accounted for as interest expense for debt.

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Including the current and noncurrent portions, aggregate carrying amount of all types of notes payable, as of the balance sheet date, with initial maturities beyond one year or beyond the normal operating cycle, if longer.

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