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Segment Reporting - Narrative (Details) - segment
3 Months Ended
Mar. 31, 2021
Mar. 31, 2020
Mar. 31, 2019
Revenue, Major Customer [Line Items]      
Number of operating segments 1 1  
Outside of the United States | Revenue | Geographic Concentration Risk      
Revenue, Major Customer [Line Items]      
Concentration risk percentage 2.00% 2.00% 2.00%