Supplemental Disclosures to the Consolidated Statements of Cash Flows (Additional Information Concerning Acquisitions, Interest and Income Taxes Paid) (Details) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023
Supplemental Cash Flow Information [Abstract]
Assets acquired, excluding cash, cash equivalents, and cash and cash equivalents held in a fiduciary capacity	$ 1,310	$ 760
Fiduciary liabilities assumed	(8)	(14)
Liabilities assumed	(84)	(98)
Contingent/deferred purchase consideration	(176)	(29)
Net cash outflow for acquisitions	1,042	619
Interest paid	538	427
Income taxes paid, net of refunds	$ 922	$ 699