Leases - Schedule of Maturities of Lease Obligations (Detail) $ in Millions	Dec. 31, 2019 USD ($)
Leases [Abstract]
Operating Leases, 2020	$ 200
Operating Leases, 2021	72
Operating Leases, 2022	65
Operating Leases, 2023	64
Operating Leases, 2024	65
Operating Leases, Remaining years	133
Total lease payments	599
Less: Imputed interest	(64)
Total lease obligations	535
Finance Leases, 2020	36
Finance Leases, 2021	36
Finance Leases, 2022	36
Finance Leases, 2023	36
Finance Leases, 2024	36
Finance Leases, Remaining years	212
Total lease payments	392
Less: Imputed interest	(137)
Total lease obligations	$ 255