Stock-Based Compensation Plans - Additional Information (Detail) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares under equity incentive compensation plan for future grant	3,168,796
Stock-based compensation expense	$ 116	$ 118	$ 111
Income tax benefits recognized	25	24	26
Cash received from exercised stock options	138	32	37
Fair value of stock-based awards granted	141	124	99
Intrinsic value of vested restricted stock and restricted stock units and exercised stock options	134	$ 96	$ 125
Unrecognized compensation cost related to non-vested awards	$ 48
Unrecognized compensation cost expected to be recognized over a weighted-average period (in years)	1 year
Directors’ Stock Compensation Programs
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares issuable under deferred compensation plans	1,811	1,979
Shares issued in connection with deferred compensation plans	22,990	27,027
Deferred Bonus Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares issuable under deferred compensation plans	9,831	10,238
Stock Purchase Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares under equity incentive compensation plan for future grant	1,871,663
Shares issued	100,964	90,575	75,232
Cash received from exercise of stock options	$ 13		$ 11
Restricted Stock
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting period	3 years	3 years	3 years
Stock Option Awards
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock options exercisable period, maximum	10 years

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