Annual report pursuant to Section 13 and 15(d)

Restricted cash (Details)

v3.7.0.1
Restricted cash (Details) - USD ($)
Dec. 31, 2016
Dec. 31, 2015
Restricted Cash and Cash Equivalents Items [Line Items]    
Restricted cash $ 11,213,640 $ 11,656,204
Securities for Bank Acceptance Bill [Member]    
Restricted Cash and Cash Equivalents Items [Line Items]    
Restricted cash 10,541,105 11,392,231
Time Deposits [Member]    
Restricted Cash and Cash Equivalents Items [Line Items]    
Restricted cash 151,083 263,973
Government Subsidy Deposit [Member]    
Restricted Cash and Cash Equivalents Items [Line Items]    
Restricted cash $ 521,452 $ 0