Investments - Net investment income (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Net Investment Income:
Investment income, before expense	$ 457	$ 1,012	$ 936	$ 1,731
Investment expense	(48)	(70)	(106)	(141)
Net investment income	409	942	830	1,590
Fixed income securities
Net Investment Income:
Investment income, before expense	531	543	1,056	1,081
Equity securities
Net Investment Income:
Investment income, before expense	31	68	37	98
Mortgage loans
Net Investment Income:
Investment income, before expense	51	54	111	107
Limited partnership interests
Net Investment Income:
Limited partnership interests	(220)	254	(412)	263
Short-term investments
Net Investment Income:
Investment income, before expense	2	26	19	52
Other
Net Investment Income:
Investment income, before expense	$ 62	$ 67	$ 125	$ 130

Interest and Dividend Income (Expenses), Operating

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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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Amount of expenses related to the generation of investment income.

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Amount, after investment expense, of income earned from investments in securities and real estate. Includes, but is not limited to, real estate investment, policy loans, dividends, and interest. Excludes realized gain (loss) on investments.

+ References

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