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Geographic Concentrations - Additional Information (Details) - United States - Geographic Concentration Risk
12 Months Ended
Dec. 31, 2019
Dec. 31, 2018
Dec. 31, 2017
Revenue      
Concentration Risk [Line Items]      
Concentration percentage 78.00% 81.00% 90.00%
Minimum | Property and Equipment      
Concentration Risk [Line Items]      
Concentration percentage 91.00% 91.00%