Supplemental Disclosures of Cash Flow Information (Details) - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Supplemental disclosures of cash flow information:
Cash and cash equivalents		$ 1,424	$ 1,262	$ 4,486
Fiduciary funds (included in fiduciary assets)		2,368	3,459	3,203
Cash and cash equivalents and fiduciary funds (included in current assets held for sale)		0	0	2
Total cash, cash equivalents and restricted cash		3,792	4,721	7,691
Increase/(decrease) in cash, cash equivalents and other restricted cash	[1]	(940)	(2,806)	1,517
Cash payments for income taxes, net		348	428	570
Cash payments for interest		223	201	212
Cash acquired		0	30	5
Supplemental disclosures of non-cash investing and financing activities:
Non-cash consideration received		0	63	0
Fair value of deferred and contingent consideration related to acquisitions		3	28	21
Non-Fiduciary [Member]
Supplemental disclosures of cash flow information:
Increase/(decrease) in cash, cash equivalents and other restricted cash		163	(3,177)	2,425
Fiduciary [Member]
Supplemental disclosures of cash flow information:
Increase/(decrease) in cash, cash equivalents and other restricted cash		$ (1,103)	$ 371	$ (908)

[1] The amounts of cash, cash equivalents and restricted cash, their respective classification on the consolidated balance sheets as well as their respective portions of the increase or decrease in cash, cash equivalents and restricted cash for each of the periods presented have been included in Note 21 — Supplemental Disclosures of Cash Flow Information.