Fair Value - Financial Instruments Carried at Fair Value on Recurring Basis (Detail) - USD ($) $ in Millions	Sep. 30, 2020	Dec. 31, 2019
Assets:
Derivatives	$ 79	$ 92
Mutual funds	50	3
Total	129	95
Liabilities:
Derivatives	69
Total	69
Level 1
Assets:
Derivatives	0	0
Mutual funds	50	3
Total	50	3
Liabilities:
Derivatives	0
Total	0
Level 2
Assets:
Derivatives	79	92
Mutual funds	0	0
Total	79	$ 92
Liabilities:
Derivatives	69
Total	$ 69