Related Party Transactions Narrative (Details) $ in Millions	12 Months Ended
Dec. 31, 2024 USD ($) tranche	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)
Other assets	$ 2,591	$ 2,534
Fixed maturity securities	41,111	40,425
Net investment income	2,497	2,264	$ 1,805
Net earned premiums	10,211	9,480	8,667
Commercial mortgage-backed
Amount of securitization	305
Related Party
Other liabilities, current	30	28
Taxes payable	17
Other assets	0	23
Related Party \| Fees and expenses of investment facilities and services
Related party transaction, amounts of transaction	60	55	51
Related Party \| Corporate services and related travel expenses
Related party transaction, amounts of transaction	1	1
Related Party \| Loews
Net earned premiums	2	$ 2	$ 3
Affiliated Entity
Fixed maturity securities	50
Affiliated Entity \| Maximum
Net investment income	1
Affiliated Entity \| Commercial mortgage-backed
Related party transaction, amounts of transaction	$ 50
Number of investment tranches \| tranche	3

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The income earned from investments in securities and property, equipment and other capital assets. It includes rent from property and equipment, dividends from shares in corporations, and interest from bonds, loans, mortgages, derivatives, commercial paper, bank accounts, certificates of deposits, treasuries, and other financial securities. It also includes realized gains and losses on trading securities.

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