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, 2023	Jun. 30, 2022
Supplemental Cash Flow Information [Abstract]
Assets acquired, excluding cash, cash equivalents, and cash and cash equivalents held in a fiduciary capacity	$ 364	$ 164
Acquisition-related deposit	0	24
Fiduciary liabilities assumed	(1)	(2)
Liabilities assumed	(63)	(24)
Contingent/deferred purchase consideration	(8)	(11)
Net cash outflow for acquisitions	292	151
Interest paid	245	215
Income taxes paid, net of refunds	$ 504	$ 437