Share-Based Compensation Plans - Performance Share Awards Narrative (Details) - Performance-based Awards - USD ($) $ / shares in Units, shares in Thousands, $ in Millions	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
PSA, vesting conditions period (in years)	3 years
Percentage of targeted amount	100.00%
Granted (in dollars per share)	$ 298	$ 311	$ 225
Shares issued (in shares)	956
Fair value of PSAs vested during the period	$ 156	$ 145	$ 112
Unamortized deferred compensation	$ 112
Weighted average remaining amortization period (in years)	1 year 3 months 18 days
Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
PSA, actual shares issued, percent	0.00%
Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
PSA, actual shares issued, percent	200.00%

Share-based Compensation Arrangement by Share-based Payment Award, Percentage Of Targeted Amount

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Share-based Compensation Arrangement by Share-based Payment Award, Shares Issued, Percent

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Share-based Compensation Arrangement by Share-based Payment Award, Vesting Conditions Period

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Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Number, after forfeiture, of shares or units issued under share-based payment arrangement. Excludes shares or units issued under employee stock ownership plan (ESOP).

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