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Revenue Recognition - Narrative (Details) - USD ($)	3 Months Ended
Revenue Recognition - Narrative (Details) - USD ($)	Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020
Disaggregation of Revenue [Line Items]
Contract with customer, liability	$ 3,600,000,000
Accounts receivable, credit loss expense (reversal)	$ 0	$ 0
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2020-10-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, remaining performance obligation, percentage	45.00%
Revenue, remaining performance obligation, period	12 months
Trade receivables
Disaggregation of Revenue [Line Items]
Accounts receivable, allowance for credit loss	$ 0		$ 0
Miscellaneous Receivables
Disaggregation of Revenue [Line Items]
Accounts receivable, allowance for credit loss	$ 0		$ 0