Supplemental Disclosures to the Consolidated Statements of Cash Flows (Additional Information Concerning Acquisitions, Interest and Income Taxes Paid) (Details) - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023
Supplemental Cash Flow Information [Abstract]
Assets acquired, excluding cash, cash equivalents, and cash and cash equivalents held in a fiduciary capacity	$ 721	$ 364
Fiduciary liabilities assumed	(5)	(1)
Liabilities assumed	(18)	(63)
Contingent/deferred purchase consideration	(54)	(8)
Net cash outflow for acquisitions	644	292
Interest paid	295	245
Income taxes paid, net of refunds	$ 658	$ 504