Revenue Recognition - Additional Information (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Disaggregation of Revenue [Line Items]
Amounts included in contract liability	$ 273	$ 42
Business Customer
Disaggregation of Revenue [Line Items]
Customer life	49 months
Minimum
Disaggregation of Revenue [Line Items]
Contract term	1 year
Minimum | Business Customer
Disaggregation of Revenue [Line Items]
Customer life	49 months
Maximum
Disaggregation of Revenue [Line Items]
Contract term	5 years
Average | Consumer Customers
Disaggregation of Revenue [Line Items]
Customer life	30 months