Employee Benefit Plans (Schedule of Fair Value Measurements By Category) (Detail) - USD ($) $ in Millions		Dec. 31, 2023	Dec. 31, 2022
Defined Benefit Plan Disclosure [Line Items]
Total recorded at fair value		$ 156	$ 157
Commingled funds/collective trust funds	[1]	436	417
Total recorded at NAV	[1]	436	417
Total investments	[2]	592	574
Level 1
Defined Benefit Plan Disclosure [Line Items]
Total recorded at fair value		4	0
Fair Value, Inputs, Level 2
Defined Benefit Plan Disclosure [Line Items]
Total recorded at fair value		152	157
Level 3
Defined Benefit Plan Disclosure [Line Items]
Total recorded at fair value		0	0
Cash and cash equivalents
Defined Benefit Plan Disclosure [Line Items]
Total recorded at fair value		5	2
Cash and cash equivalents | Level 1
Defined Benefit Plan Disclosure [Line Items]
Total recorded at fair value		4	0
Cash and cash equivalents | Fair Value, Inputs, Level 2
Defined Benefit Plan Disclosure [Line Items]
Total recorded at fair value		1	2
Cash and cash equivalents | Level 3
Defined Benefit Plan Disclosure [Line Items]
Total recorded at fair value		0	0
Corporate Debt Securities
Defined Benefit Plan Disclosure [Line Items]
Total recorded at fair value		137	137
Corporate Debt Securities | Level 1
Defined Benefit Plan Disclosure [Line Items]
Total recorded at fair value		0	0
Corporate Debt Securities | Fair Value, Inputs, Level 2
Defined Benefit Plan Disclosure [Line Items]
Total recorded at fair value		137	137
Corporate Debt Securities | Level 3
Defined Benefit Plan Disclosure [Line Items]
Total recorded at fair value		0	0
Government and Other Debt Instruments
Defined Benefit Plan Disclosure [Line Items]
Total recorded at fair value		14	18
Government and Other Debt Instruments | Level 1
Defined Benefit Plan Disclosure [Line Items]
Total recorded at fair value		0	0
Government and Other Debt Instruments | Fair Value, Inputs, Level 2
Defined Benefit Plan Disclosure [Line Items]
Total recorded at fair value		14	18
Government and Other Debt Instruments | Level 3
Defined Benefit Plan Disclosure [Line Items]
Total recorded at fair value		$ 0	$ 0

[1] These investments that are measured at fair value using the NAV per share (or its equivalent) as a practical expedient are not required to be categorized in the fair value hierarchy.

[2] Excludes net assets related to pending sales of securities of $1 million, net accrued income of $1 million, and includes net assets related to pending purchases of securities of $6 million at December 31, 2023. Excludes net assets related to pending sales of securities of $1 million, net accrued income of $1 million, and includes net assets related to pending purchases of securities of $15 million at December 31, 2022.