Quarterly report pursuant to Section 13 or 15(d)

Stockholders' equity (Details)

v3.7.0.1
Stockholders' equity (Details) - USD ($)
1 Months Ended 3 Months Ended 6 Months Ended
Mar. 31, 2017
Jun. 30, 2017
Jun. 30, 2016
Jun. 30, 2017
Jun. 30, 2016
Dec. 31, 2016
Class of Stock [Line Items]            
Proceeds from issuance of common stock       $ 1,913,509  
Interest rate percentage   4.50%   4.50%    
Interest expense   $ 24,065 $ 148 $ 28,899 $ 25,746  
Accrued interest   $ 27,589   $ 27,589  
Rights forfeited       532,911    
Total consideration under the agreements forfeited during period       $ 299,500    
Total consideration under the agreements forfeited during period charged to equity       291,995    
Total consideration under the agreements forfeited during period recorded as compensation       $ 7,505    
Dividend yield       0.00% 0.00%  
Expected price volatility, minimum       49.00%    
Expected price volatility, maximum       99.00%    
Risk free interest rates, minimum       0.80%    
Risk free interest rates, maximum       2.30%    
2002 Stock Incentive Plan [Member]            
Class of Stock [Line Items]            
Rights forfeited       494,578    
BDI [Member]            
Class of Stock [Line Items]            
Number of common shares previously held in escrow, cancelled during period       32,801    
Estimated value of common shares recoded resulting in a reduction in impairment loss       $ 134,812    
Share price   $ 4.11   $ 4.11    
Private Placement [Member]            
Class of Stock [Line Items]            
Proceeds from private placement       $ 7,000,000    
Total amount of financing from common stock units   $ 2,250,000   2,250,000    
Proceeds from issuance of common stock $ 2,250,000     $ 1,000,000    
Issuance of common stock       400,000    
Offering expenses incurred from private placement stock issuance       $ 336,491    
Common stock shares held in escrow   500,000   500,000    
Proceeds from common stock and warrants released       $ 1,250,000    
Purchase price   $ 2.50   $ 2.50    
Private Placement [Member] | Convertible Note [Member]            
Class of Stock [Line Items]            
Debt instrument face amount   $ 4,750,000   $ 4,750,000    
Conversion price   $ 2.50   $ 2.50    
Interest rate percentage   2.00%   2.00%    
Interest expense   $ 23,700   $ 27,600    
Accrued interest   $ 27,600   $ 27,600    
Private Placement [Member] | Warrant [Member]            
Class of Stock [Line Items]            
Exercise price of warrants   $ 3.56   $ 3.56    
Warrants to purchase common stock   1,900,000   1,900,000    
Warrant to purchase term       3 years    
Restricted Stock [Member]            
Class of Stock [Line Items]            
Award of restricted shares       197,000    
Shares terminated       40,000    
Common shares vested       21,333    
Warrant to purchase term       24 months    
Rights forfeited       833    
Non-qualified stock option awards [Member]            
Class of Stock [Line Items]            
Rights forfeited       37,500