Revenue Recognition - Additional Information - Customer Receivables and Contract Balances (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Customer Receivables and Contract Balances [Line Items]
Revenue recognized from prior year contract liability	$ 12	$ 13	$ 175	$ 197
Minimum
Customer Receivables and Contract Balances [Line Items]
Contract term			1 year
Maximum
Customer Receivables and Contract Balances [Line Items]
Contract term			5 years