Fair Value Measurements - Measured on Recurring Basis (Detail) - Fair Value, Measurements, Recurring - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Assets
Derivatives	$ 32	$ 18
Liabilities
Derivatives	200	196
Mutual funds
Assets
Fair value of investments measured on recurring basis	1,025	897
U.S. Government securities
Assets
Fair value of investments measured on recurring basis	119	118
Other securities
Assets
Fair value of investments measured on recurring basis	679	660
Level 1
Assets
Derivatives	0	0
Liabilities
Derivatives	0	0
Level 1 | Mutual funds
Assets
Fair value of investments measured on recurring basis	1,025	897
Level 1 | U.S. Government securities
Assets
Fair value of investments measured on recurring basis	0	0
Level 1 | Other securities
Assets
Fair value of investments measured on recurring basis	333	333
Level 2
Assets
Derivatives	32	18
Liabilities
Derivatives	200	196
Level 2 | Mutual funds
Assets
Fair value of investments measured on recurring basis	0	0
Level 2 | U.S. Government securities
Assets
Fair value of investments measured on recurring basis	119	118
Level 2 | Other securities
Assets
Fair value of investments measured on recurring basis	301	264
Level 3
Assets
Derivatives	0	0
Liabilities
Derivatives	0	0
Level 3 | Mutual funds
Assets
Fair value of investments measured on recurring basis	0	0
Level 3 | U.S. Government securities
Assets
Fair value of investments measured on recurring basis	0	0
Level 3 | Other securities
Assets
Fair value of investments measured on recurring basis	$ 45	$ 63