Unaudited Consolidated Statements of Cash Flows - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023
Operating Activities
Net income (loss)	$ 2,389	$ 1,386
Adjustments to reconcile net income (loss) to net cash provided by operating activities:
Net realized (gains) losses	(196)	110
Equity in net (income) or loss of investment funds accounted for using the equity method and other income or loss	(174)	(49)
Amortization of intangible assets	48	47
Share-based compensation	84	58
Changes in:
Reserve for losses and loss adjustment expenses, net of unpaid losses and loss adjustment expenses recoverable	1,369	1,020
Unearned premiums, net of ceded unearned premiums	879	1,004
Premiums receivable	(1,682)	(1,648)
Deferred acquisition costs	(80)	(152)
Reinsurance balances payable	616	652
Deferred income tax assets, net	45	58
Other items, net	(216)	(372)
Net cash provided by operating activities	3,082	2,114
Investing Activities
Purchases of fixed maturity investments	(14,123)	(8,840)
Purchases of equity securities	(654)	(104)
Purchases of other investments	(1,369)	(557)
Proceeds from sales of fixed maturity investments	11,220	7,079
Proceeds from sales of equity securities	547	161
Proceeds from sales, redemptions and maturities of other investments	619	201
Proceeds from redemptions and maturities of fixed maturity investments	878	368
Net settlements of derivative instruments	12	46
Net (purchases) sales of short-term investments	(25)	(333)
Purchases of fixed assets	(26)	(26)
Other	3	4
Net cash used for investing activities	(2,918)	(2,001)
Financing Activities
Proceeds from common shares issued, net	(8)	0
Change in third party investment in redeemable noncontrolling interests	0	(22)
Other	0	(3)
Preferred dividends paid	(20)	(20)
Net cash used for financing activities	(28)	(45)
Effects of exchange rate changes on foreign currency cash and restricted cash	(7)	12
Increase (decrease) in cash and restricted cash	129	80
Cash and restricted cash, beginning of year	1,498	1,273
Cash and restricted cash, end of period	1,627	1,353
Income taxes paid (received)	145	73
Interest paid	$ 63	$ 63