Income taxes (restated) (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
U.S. federal tax loss carry-forward	$ 6,400	$ 5,858
U.S. State tax loss carry-forward	224	74
Foreign tax loss carry-forward	15,552	15,968
U.S. federal capital loss carry-forward	706	671
Equity-based compensation, fixed assets and other	255	104
Total deferred tax assets	23,137	22,675
Less: valuation allowance	(22,917)	(22,675)
Subtotal	220	0
Deferred Tax Liability
Warrants	(220)	0
Net deferred tax asset	$ 0	$ 0

Amount before allocation of valuation allowances of deferred tax liability warrants to taxable temporary differences.

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Amount after allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards, net of deferred tax liability attributable to taxable temporary differences.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible domestic operating loss carryforwards. Excludes state and local operating loss carryforwards.

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Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized.

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