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Supplemental Disclosures of Cash Flow Information (Details) - USD ($) $ in Millions		9 Months Ended
		Sep. 30, 2025	Sep. 30, 2024	Dec. 31, 2024
Supplemental disclosures of cash flow information:
Cash and cash equivalents		$ 1,895	$ 1,372	$ 1,890
Fiduciary funds (included in fiduciary assets)		3,528	3,340
Total cash, cash equivalents and restricted cash		5,423	4,712
Decrease in cash, cash equivalents and other restricted cash	[1]	223	888
Non-Fiduciary [Member]
Supplemental disclosures of cash flow information:
Decrease in cash, cash equivalents and other restricted cash		(66)	(54)
Fiduciary [Member]
Supplemental disclosures of cash flow information:
Decrease in cash, cash equivalents and other restricted cash		$ 289	$ 942
[1] The amounts of cash, cash equivalents and restricted cash, their respective classification on the condensed 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 19 — Supplemental Disclosures of Cash Flow Information.

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