Investments and Cash - 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
Gross investment income	$ 80	$ 112	$ 162	$ 212
Investment expenses	(2)	(2)	(4)	(4)
Net investment income	78	110	158	208
Securities, Managed Externally [Member]
Net Investment Income
Gross investment income	62	69	124	141
Investments, Managed Internally [Member]
Net Investment Income
Gross investment income	$ 18	$ 43	$ 38	$ 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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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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