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Share Transactions - Share-based compensation (Details) - $ / shares shares in Millions	3 Months Ended
	Mar. 31, 2025	Mar. 31, 2024
Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Grants during period, options (shares)	0.4	0.4
Weighted average grant date fair value, options (per share)	$ 32.46	$ 30.73
Performance shares and units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Grants during period, other than options (shares)	0.5	0.5
Weighted average grant date fair value, other than options (per share)	$ 93.26	$ 93.28
Restricted shares and units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Grants during period, other than options (shares)	0.7	0.7
Weighted average grant date fair value, other than options (per share)	$ 91.87	$ 87.22

X

- Definition

The number of grants made 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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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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Gross number of share options (or share units) granted during the period.

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The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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