Annual report pursuant to Section 13 and 15(d)

Summary of significant accounting policies - Fair value using the Black-Scholes pricing model (Details)

v3.10.0.1
Summary of significant accounting policies - Fair value using the Black-Scholes pricing model (Details) - $ / shares
3 Months Ended 6 Months Ended 12 Months Ended
Sep. 30, 2017
Mar. 31, 2017
Jun. 30, 2017
Dec. 31, 2017
Dec. 31, 2016
Dec. 31, 2015
Accounting Policies [Abstract]            
Stock Price $ 0.031 $ 0.041 $ 0.046 $ 0.042 $ 0.0513 $ 0.10
Expected volatility 89.65% 94.99% 94.91% 89.33% 104.69% 91.30%
Risk-free Interest 1.06% 0.76% 1.03% 1.39% 0.51% 0.04%
Annual Dividend Yield 0.00% 0.00% 0.00% 0.00% 0.00% 0.00%
Exepected Life (years) 1 year 7 months 1 year 8 months 9 days 1 year 2 months 6 days 1 year 9 months 6 days 1 year 3 months 1 day 1 day