Annual report pursuant to Section 13 and 15(d)

Intangible assets - Narrative (Details)

v3.3.1.900
Intangible assets - Narrative (Details) - USD ($)
 12 Months Ended
Dec. 31, 2015
Dec. 31, 2014
Acquired Finite-Lived Intangible Assets [Line Items]    
Amortization expense $ 99,721 $ 83,986
Product Certifications    
Acquired Finite-Lived Intangible Assets [Line Items]    
Capitalized finited lived intangible assets 39,272 68,638
Patents    
Acquired Finite-Lived Intangible Assets [Line Items]    
Capitalized finited lived intangible assets $ 88,985 $ 73,321
Patents | Minimum    
Acquired Finite-Lived Intangible Assets [Line Items]    
Finited lived intangible assets, estimated useful life 7 years  
Patents | Maximum    
Acquired Finite-Lived Intangible Assets [Line Items]    
Finited lived intangible assets, estimated useful life 10 years