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Share Transactions - Share-based compensation (Details) - $ / shares shares in Millions | 3 Months Ended
--- | ---
Mar. 31, 2024 | Mar. 31, 2023
Stock options |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |
Grants during period, options (shares) | 0.4 | 0.5
Weighted average grant date fair value, options (per share) | $ 30.73 | $ 23.49
Performance shares and units |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |
Grants during period, other than options (shares) | 0.5 | 0.6
Weighted average grant date fair value, other than options (per share) | $ 93.28 | $ 74.06
Restricted shares and units |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |
Grants during period, other than options (shares) | 0.7 | 0.8
Weighted average grant date fair value, other than options (per share) | $ 87.22 | $ 69.25

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). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 718 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (c)(2)(iii)(01) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480429/718-10-50-2 + Details
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- Definition 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). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 718 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (c)(2)(iii)(01) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480429/718-10-50-2 + Details
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- Definition Line items represent financial concepts included in a table. 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