Consolidated Statements Of Cash Flows - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Adjustments to reconcile net income to net cash flows from operating activities
Net Realized Gains Losses	$ 607	$ 1,085	$ (1,030)
Accretion (Amortization) of Discounts and Premiums, Investments	(148)	189	332
Amortization of purchased intangibles	310	285	287
Deferred income taxes	(1,124)	318	(84)
Equity in net income of subsidiaries and affiliates	(867)	(1)	(2,435)
Unpaid losses and loss expenses	3,470	4,259	5,178
Unearned premiums	1,377	1,435	1,252
Future policy benefits	848	333	1,040
Insurance and reinsurance balances payable	(155)	446	582
Accounts payable, accrued expenses, and other liabilities	(735)	(68)	(2,423)
Income taxes	128	(149)	48
Insurance and reinsurance balances receivable	(1,072)	(696)	(984)
Reinsurance recoverable	(498)	(1,737)	(1,949)
Deferred policy acquisition costs	(1,100)	(396)	(422)
Net sales of investments by consolidated investment products	450	0	0
Other	1,819	789	3,325
Net Cash Provided by (Used in) Operating Activities, Total	12,632	11,258	11,151
Cash flows from investing activities
Purchases of fixed maturities available-for-sale	(28,672)	(27,844)	(30,222)
Purchases of fixed maturities held to maturity	(208)	(618)	(594)
Purchases of equity securities	(1,395)	(895)	(1,167)
Sales of fixed maturities available-for-sale	14,593	16,855	6,596
Sales of equity securities	1,084	4,615	1,018
Maturities and redemptions of fixed maturities available-for-sale	7,026	9,415	17,361
Maturities and redemptions of fixed maturities held to maturity	708	1,712	1,964
Net change in short-term investments	1,169	(1,452)	1,175
Net derivative instruments settlements	(153)	(84)	(219)
Private equity contributions	(2,024)	(2,649)	(2,471)
Private equity distributions	1,164	1,017	1,421
Acquisition of subsidiaries (net of cash acquired of $560, $366, and nil)	(34)	(5,166)	(1,184)
Cash And Cash Equivalents Increase (Decrease) Due To Consolidation And Deconsolidation Of Investment Products	(17)	0	0
Other	(889)	(560)	(337)
Net Cash Provided by (Used in) Investing Activities	(7,648)	(5,654)	(6,659)
Cash flows from financing activities
Dividends paid on Common Shares	(1,394)	(1,375)	(1,401)
Common Shares repurchased	(2,411)	(2,894)	(4,861)
Proceeds from issuance of long-term debt	0	0	1,576
Proceeds from issuance of repurchase agreements	4,984	4,510	1,858
Repayments of Long-term Debt	(475)	(1,000)	0
Repayment of repurchase agreements	(4,728)	(4,508)	(1,858)
Proceeds from share-based compensation plans	212	264	300
Policyholder contract deposits	645	488	513
Policyholder contract withdrawals	(458)	(521)	(457)
Third-party capital invested into consolidated investment products	126	0	0
Third-party capital distributed by consolidated investment products	(745)	0	0
Tax withholding payments for share-based compensation plans	(245)	(106)	(81)
Net cash flows (used for) from financing activities	(4,489)	(5,142)	(4,411)
Effect of foreign currency rate changes on cash and restricted cash	(1)	(146)	(106)
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents, Period Increase (Decrease), Including Exchange Rate Effect	494	316	(25)
Cash and restricted cash - beginning of year	2,127	1,811	1,836
Cash and restricted cash - end of year	2,621	2,127	1,811
Supplemental cash flow information
Taxes paid	1,465	1,242	1,298
Interest paid	553	552	492
Market Risk Benefit, Change in Fair Value, Gain (Loss)	307	(80)	(91)
Net income	$ 9,015	$ 5,246	$ 8,525