Employee Benefit Plans (Components of Net Periodic Benefit Cost) (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 8	$ 8	$ 9
Interest cost	33	21	20
Expected return on assets	(34)	(49)	(48)
Amortization of actuarial losses (gains)	12	1	6
Net periodic benefit cost	19	(19)	(13)
Other Postretirement Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	1	1	1
Interest cost	8	6	6
Expected return on assets	0	0	0
Amortization of actuarial losses (gains)	(4)	0	0
Net periodic benefit cost	$ 5	$ 7	$ 7