Investments - Schedule of Net Investment Income (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Net Investment Income:
Investment income, before expense	$ 1,092	$ 823	$ 2,102	$ 1,748
Investment expense	(83)	(69)	(155)	(140)
Net investment income	1,009	754	1,947	1,608
Fixed income securities
Net Investment Income:
Investment income, before expense	710	602	1,376	1,210
Equity securities
Net Investment Income:
Investment income, before expense	54	17	95	37
Mortgage loans
Net Investment Income:
Investment income, before expense	12	9	24	19
Limited partnership interests
Net Investment Income:
Investment income, before expense	240	74	446	268
Short-term investments
Net Investment Income:
Investment income, before expense	48	97	107	169
Other investments
Net Investment Income:
Investment income, before expense	$ 28	$ 24	$ 54	$ 45

Represents the total of interest and dividend income, including any amortization and accretion (as applicable) of discounts and premiums, earned from (1) loans and leases whether held-for-sale or held-in-portfolio; (2) investment securities; (3) federal funds sold; (4) securities purchased under agreements to resell; (5) investments in banker's acceptances, commercial paper, or certificates of deposit; (6) dividend income; or (7) other investments not otherwise specified herein.

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