Annual report pursuant to Section 13 and 15(d)

Summary of significant accounting policies - Fair value of financial instruments (Details)

v3.10.0.1
Summary of significant accounting policies - Fair value of financial instruments (Details) - USD ($)
Dec. 31, 2017
Sep. 30, 2017
Jun. 30, 2017
Mar. 31, 2017
Dec. 31, 2016
Dec. 31, 2015
Dec. 31, 2014
Derivative liabilities $ 826,782 $ 108,742 $ 381,396 $ 577,241 $ 1,302,543 $ 1,868,439 $ 547,940
Quoted Prices in Active Markets for Identical Assets or Liabilities-Level 1 [Member]              
Derivative liabilities  
Quoted Prices for Similar Assets or Liabilities in Active Markets - Level 2 [Member]              
Derivative liabilities  
Significant Unobservable Inputs - Level 3 [Member]              
Derivative liabilities $ 826,782 $ 377,571 $ 381,396 $ 577,241 $ 1,302,543 $ 1,868,439