Net income (loss) per common share - Basic and Diluted Earnings (Details 1) - USD ($)	3 Months Ended	9 Months Ended
Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Basic earnings per share
Net loss per share from continuing operations, amount	$ (2,394,146)	$ 78,389	$ (6,541,761)	$ (5,738,985)
Net loss per share from continuing operations, number of shares	124,089,230	119,407,668	123,852,105	102,455,451
Net loss per share from continuing operations, per share	$ (0.02)		$ (0.05)	$ (0.06)
Net income per share from discontinued operations, number of shares	124,089,230	119,407,668	123,852,105	102,455,451
Net income per share from discontinued operations, per share				$ 0.07
Diluted earnings per share
Net loss per share from continuing operations, amount	$ (2,394,146)	$ 78,389	$ (6,541,761)	$ (5,738,985)
Net loss per share from continuing operations, per share	$ (0.02)		$ (0.05)	$ (0.05)
Net income per share from discontinued operations, number of shares	124,089,230	119,407,668	123,852,105	117,312,150
Net Income Per Share [Member]
Basic earnings per share
Net loss per share from continuing operations, amount				$ (5,738,985)
Net loss per share from continuing operations, number of shares				102,455,451
Net loss per share from continuing operations, per share				$ (0.06)
Net income per share from discontinued operations, amount				$ 7,194,389
Net income per share from discontinued operations, number of shares				102,455,451
Net income per share from discontinued operations, per share				$ 0.07
Effect of dilutive securities
Warrants, number of shares				14,856,699
Diluted earnings per share
Net loss per share from continuing operations, amount				$ (5,738,985)
Net loss per share from continuing operations, number of shares				117,312,150
Net loss per share from continuing operations, per share				$ (0.05)
Net income per share from discontinued operations, amount				$ 7,194,389
Net income per share from discontinued operations, number of shares				117,312,150
Net income per share from discontinued operations, per share				$ 0.06

The amount of discontinued operation gain (loss) on disposal of discountinued operation net of tax.

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The amount of net income (loss) from continuing operations per each share of common stock or unit outstanding during the reporting period.

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