Investments - Schedule of Net Investment Income (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Net Investment Income:
Investment income, before expense	$ 788	$ 681	$ 1,625	$ 1,331
Investment expense	(76)	(71)	(149)	(146)
Net investment income	712	610	1,476	1,185
Fixed income securities
Net Investment Income:
Investment income, before expense	571	422	1,097	812
Equity securities
Net Investment Income:
Investment income, before expense	18	21	33	32
Mortgage loans
Net Investment Income:
Investment income, before expense	9	8	18	16
Limited partnership interests
Net Investment Income:
Investment income, before expense	103	122	302	256
Short-term investments
Net Investment Income:
Investment income, before expense	62	69	129	135
Other investments
Net Investment Income:
Investment income, before expense	$ 25	$ 39	$ 46	$ 80

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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