Non-controlling interest (Details 1) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011
Net loss attributable to MGT Capital Investments, Inc.	$ (1,026)	$ (1,450)	$ (1,496)	$ (2,942)
Transfers (to) from the non-controlling interest:
Increase in MGT's paid in capital from sale and assignment of Medicsight's stock			0	21
Increase in MGT's paid in capital from Medicsight Share Consolidation			2,392	0
Changes from the net loss attributable to MGT Capital Investments, Inc. and transfers from non-controlling interest			$ 896	$ (2,921)