XML 57 R44.htm IDEA: XBRL DOCUMENT v3.10.0.1
Description of the Business and Summary of Significant Accounting Policies - Concentrations of Credit Risk (Details) - Customer Concentration Risk - Trade and Other Receivables
12 Months Ended
Dec. 31, 2018
Dec. 31, 2017
Customer A    
Concentration Risk [Line Items]    
Concentration risk, percentage 14.00% 18.00%
Customer B    
Concentration Risk [Line Items]    
Concentration risk, percentage 23.00% 27.00%