Annual report pursuant to Section 13 and 15(d)

Income taxes - Domestic and foreign components of income (loss) before income taxes (Details)

v3.10.0.1
Income taxes - Domestic and foreign components of income (loss) before income taxes (Details) - USD ($)
12 Months Ended
Dec. 31, 2017
Dec. 31, 2016
Dec. 31, 2015
Income Tax Disclosure [Abstract]      
Domestic $ (2,618,595) $ (2,244,052) $ (9,713,671)
Foreign (1,462,534) (1,912,164) (715,095)
Loss from continuing operation before provision for income taxes $ (4,081,129) $ (4,156,216) $ (10,428,766)