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Employee Benefits - Schedule of Expense Recognized in Compensation and Benefit in the Consolidated Statements of Income (Details) - USD ($) $ in Millions | 12 Months Ended
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Dec. 31, 2024 | Dec. 31, 2023 | Dec. 31, 2022
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |
Expense recognized for defined contribution savings plans | $ 212 | $ 199 | $ 188
U.S. |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |
Expense recognized for defined contribution savings plans | 124 | 114 | 108
U.K. |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |
Expense recognized for defined contribution savings plans | 55 | 52 | 47
Netherlands and Canada |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |
Expense recognized for defined contribution savings plans | $ 33 | $ 33 | $ 33

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- Definition Amount of cost for defined contribution plan. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 70 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org/1943274/2147480794/715-70-50-1 + Details
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