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Summary of Significant Accounting Policies - Narrative (Details) - USD ($)
$ in Millions
3 Months Ended 12 Months Ended
Mar. 31, 2021
Dec. 31, 2020
New Accounting Pronouncements or Change in Accounting Principle [Line Items]    
Restricted cash $ 1 $ 0
Revenue from Contract with Customer | Customer Concentration Risk | Four Largest Customers    
New Accounting Pronouncements or Change in Accounting Principle [Line Items]    
Concentration risk, percentage 47.00% 61.00%
Accounts Receivable | Customer Concentration Risk | Four Largest Customers    
New Accounting Pronouncements or Change in Accounting Principle [Line Items]    
Concentration risk, percentage 35.00% 40.00%