CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (UNAUDITED) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Cash flows from operating activities:
Net income before non-controlling interests	$ 293	$ 236
Adjustments to reconcile net income before non-controlling interest to net cash provided by operating activities:
Amortization	43	41
Depreciation	11	10
Non-cash stock-based compensation	29	24
Change in estimated acquisition earn-out payables	(2)	(2)
Deferred income taxes	(1)	1
Net loss/(gain) on sales/disposals of investments, fixed assets and customer accounts	2	(5)
Payments on acquisition earn-outs in excess of original estimated payables	(13)
Changes in operating assets and liabilities, net of effect from acquisitions and divestitures:
Commissions, fees and other receivables (increase) decrease	(142)	(131)
Reinsurance recoverable (increase) decrease	60	688
Prepaid reinsurance premiums (increase) decrease	33	14
Other assets (increase) decrease	0	(6)
Losses and loss adjustment reserve increase (decrease)	(59)	(687)
Unearned premiums increase (decrease)	25	(13)
Accounts payable increase (decrease)	(86)	71
Accrued expenses and other liabilities increase (decrease)	(186)	(169)
Other liabilities increase (decrease)	6	(12)
Net cash provided by operating activities	13	60
Cash flows from investing activities:
Additions to fixed assets	(13)	(12)
Payments for businesses acquired, net of cash acquired	(76)	(38)
Proceeds from sales of fixed assets and customer accounts		6
Purchases of investments		(3)
Proceeds from sales of investments	1	4
Net cash used in investing activities	(88)	(43)
Cash flows from financing activities:
Fiduciary receivables and liabilities, net	(26)	(19)
Payments on acquisition earn-outs	(39)	(16)
Payments on long-term debt	(13)	(17)
Borrowings on revolving credit facility	150
Payments on revolving credit facilities	(50)
Repurchase shares to fund tax withholdings for non-cash stock-based compensation	(54)	(36)
Cash dividends paid	(38)	(33)
Non-controlling interest acquired (disposed), net	3
Net cash used in financing activities	(67)	(121)
Effect of foreign exchange rate changes on cash and cash equivalents inclusive of fiduciary cash	(11)	14
Net decrease in cash and cash equivalents inclusive of fiduciary cash	(153)	(90)
Cash and cash equivalents inclusive of fiduciary cash at beginning of period	2,303	2,033
Cash and cash equivalents inclusive of fiduciary cash at end of period	$ 2,150	$ 1,943