Revenues - Additional Information (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019
Revenue from Contract with Customer [Abstract]
Revenues recognized from performance obligations satisfied in prior periods	$ 206	$ 201	$ 618	$ 527
Contract with customer, performance obligation satisfied in previous period	13	$ 9	94	$ 309
Contract assets	186		186		$ 144
Contract liabilities	$ 103		$ 103		$ 45