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Summary of Significant Accounting Policies (Details)
12 Months Ended
Dec. 31, 2018
Dec. 31, 2017
Purchaser A [Member]    
Concentration Risk [Line Items]    
Percentages by purchaser 17.00%  
Purchaser E [Member]    
Concentration Risk [Line Items]    
Percentages by purchaser 16.00%
Purchaser B [Member]    
Concentration Risk [Line Items]    
Percentages by purchaser 12.00% 17.00%
Purchaser C [Member]    
Concentration Risk [Line Items]    
Percentages by purchaser 9.00% 12.00%
Purchaser D [Member]    
Concentration Risk [Line Items]    
Percentages by purchaser 8.00% 11.00%