Income taxes (Details 2)	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Effective Income Tax Rate Reconciliation [Line Items]
Expected Federal Tax	(34.00%)	(34.00%)
State Tax (Net of Federal Benefit)	(5.48%)	(6.63%)
Effective Income Tax Rate Reconciliation Permanant Differences	0.12%	1.98%
Loss of NOL benefit of closed foreign entity	0.00%	142.44%
Write-off of deferred tax asset	4.29%	0.00%
Adjustments to deferred tax balances	(8.34%)	0.00%
Foreign tax credit	0.00%	(1.60%)
Other	0.05%	1.78%
Change in valuation allowance	43.36%	103.98%
Effective rate of income tax	0.00%	0.00%

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Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) attributable to loss of net operating loss benefit of closed foreign entity.

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Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) attributable to permanant differences.

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Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to deductions. Including, but not limited to, extraterritorial income exclusion deduction, qualified production activity deduction, dividend deduction, deduction for dividend paid to employee stock ownership plan, Medicare prescription drug benefit subsidy deduction, and other deductions.

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