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Revenues - Narrative (Details)
3 Months Ended 12 Months Ended
Mar. 31, 2021
Mar. 31, 2020
Dec. 31, 2020
Dec. 31, 2019
One customer | Customer concentration risk | Revenue        
Disaggregation of Revenue [Line Items]        
Concentration risk 96.50% 96.60% 79.10% 100.00%