Investments - Schedule of Net Investment Income (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2026	Sep. 30, 2025	Sep. 30, 2026	Sep. 30, 2025
Net Investment Income:
Investment income, before expense	$ 1,255	$ 1,020	$ 3,357	$ 2,768
Investment expense	(78)	(71)	(233)	(211)
Net investment income	1,177	949	3,124	2,557
Fixed income securities
Net Investment Income:
Investment income, before expense	759	634	2,135	1,844
Equity securities
Net Investment Income:
Investment income, before expense	53	19	148	56
Mortgage loans
Net Investment Income:
Investment income, before expense	15	11	39	30
Limited partnership interests
Net Investment Income:
Investment income, before expense	354	226	800	494
Short-term investments
Net Investment Income:
Investment income, before expense	48	104	155	273
Other investments
Net Investment Income:
Investment income, before expense	$ 26	$ 26	$ 80	$ 71

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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