Leases - 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
Range [Axis] [Line Items]
Operating Lease, Weighted Average Remaining Lease Term	5 years		5 years		5 years
Document Period End Date			Sep. 30, 2020
Operating lease expenses	$ 8	$ 9	$ 24	$ 28