Quarterly report pursuant to Section 13 or 15(d)

Fair value of financial instruments (Details 2)

v3.19.2
Fair value of financial instruments (Details 2) - USD ($)
Jun. 30, 2019
Dec. 31, 2018
Investments, Fair Value Disclosure [Abstract]    
Assets, Fair Value $ 215,000  
Fair Value, Measurements, Nonrecurring [Member] | Fair Value, Inputs, Level 1 [Member]    
Investments, Fair Value Disclosure [Abstract]    
Assets, Fair Value   $ 0
Fair Value, Measurements, Nonrecurring [Member] | Fair Value, Inputs, Level 1 [Member] | Convertible Notes Receivable [Member]    
Investments, Fair Value Disclosure [Abstract]    
Assets, Fair Value   0
Fair Value, Measurements, Nonrecurring [Member] | Fair Value, Inputs, Level 2 [Member]    
Investments, Fair Value Disclosure [Abstract]    
Assets, Fair Value   0
Fair Value, Measurements, Nonrecurring [Member] | Fair Value, Inputs, Level 2 [Member] | Convertible Notes Receivable [Member]    
Investments, Fair Value Disclosure [Abstract]    
Assets, Fair Value   0
Fair Value, Measurements, Nonrecurring [Member] | Fair Value, Inputs, Level 3 [Member]    
Investments, Fair Value Disclosure [Abstract]    
Assets, Fair Value   904,317
Fair Value, Measurements, Nonrecurring [Member] | Fair Value, Inputs, Level 3 [Member] | Convertible Notes Receivable [Member]    
Investments, Fair Value Disclosure [Abstract]    
Assets, Fair Value   837,317
Investment in Warrants [Member] | Fair Value, Measurements, Nonrecurring [Member] | Fair Value, Inputs, Level 1 [Member]    
Investments, Fair Value Disclosure [Abstract]    
Assets, Fair Value   0
Investment in Warrants [Member] | Fair Value, Measurements, Nonrecurring [Member] | Fair Value, Inputs, Level 2 [Member]    
Investments, Fair Value Disclosure [Abstract]    
Assets, Fair Value   0
Investment in Warrants [Member] | Fair Value, Measurements, Nonrecurring [Member] | Fair Value, Inputs, Level 3 [Member]    
Investments, Fair Value Disclosure [Abstract]    
Assets, Fair Value   $ 67,000