Acquisitions and Dispositions (Allocation Of Acquisition Costs) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Business Acquisition [Line Items]
Cash	$ 579	$ 888
Estimated fair value of deferred/contingent consideration	120	153	$ 183
Fair value of previously-held equity method investment	6	390	0
Total consideration	705	1,400
Allocation of purchase price:
Goodwill	16,251	$ 16,317	$ 15,517
Current Fiscal Period Acquisitions
Business Acquisition [Line Items]
Cash	579
Estimated fair value of deferred/contingent consideration	120
Fair value of previously-held equity method investment	6
Total consideration	705
Allocation of purchase price:
Cash and cash equivalents	25
Cash and cash equivalents held in a fiduciary capacity	6
Net receivables	32
Other current assets	3
Goodwill	460
Other intangible assets	228
Fixed assets, net	3
Right of use assets	7
Other assets	1
Total assets acquired	765
Current liabilities	35
Fiduciary liabilities	6
Long-term lease liabilities	7
Other liabilities	7
Total liabilities assumed	55
Non-controlling interests	5
Net assets acquired	$ 705