Leases - Maturities (Detail) $ in Millions	Jun. 30, 2019 USD ($)
Operating
2019 (excluding six months ended June 30, 2019)	$ 45
2020	87
2021	55
2022	45
2023	37
Thereafter	268
Total lease payments	537
Less: interest	(148)
Discounted lease liabilities	389
Operating leases not yet commenced	$ 167
Operating leases not yet commenced term	15 years
Financing
2019 (excluding six months ended June 30, 2019)	$ 22
2020	42
2021	40
2022	39
2023	38
Thereafter	235
Total lease payments	416
Less: interest	(87)
Discounted lease liabilities	$ 329