Supplemental Disclosures to the Consolidated Statements of Cash Flows (Supplemental Cash Flow Disclosures) (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2026	Mar. 31, 2025
Supplemental Cash Flow Information [Abstract]
Assets acquired, excluding cash, cash equivalents, and cash and cash equivalents held in a fiduciary capacity	$ 48	$ 65
Fiduciary liabilities assumed	(1)	(15)
Liabilities assumed	(4)	(7)
Fair value of previously-held equity investment	0	(15)
Contingent/deferred purchase consideration	(2)	(10)
Net cash outflow for acquisitions	41	18
Interest paid	343	317
Income taxes paid, net of refunds	$ 238	$ 237

Business Combination, Consideration, Contingent And Deferred Purchase Consideration

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Business Combination, Consideration Transferred Assets Acquired

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Business Combination, Consideration Transferred, Fair Value Of Previously-Held Equity Method Investment

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Business Combination, Consideration Transferred, Fiduciary Liabilities Assumed

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Business Combination, Consideration Transferred, Liabilities Assumed

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Amount, after refund, of cash paid to foreign, federal, state, and local jurisdictions as income tax.

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-Topic 230
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-Name Accounting Standards Codification
-Section 50
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Amount of cash paid for interest, excluding capitalized interest, classified as operating activity. Includes, but is not limited to, payment to settle zero-coupon bond for accreted interest of debt discount and debt instrument with insignificant coupon interest rate in relation to effective interest rate of borrowing attributable to accreted interest of debt discount.

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The cash outflow associated with the acquisition of a business, net of the cash acquired from the purchase.

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