Investments (Net Inv Inc summary) (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Net Investment Income [Line Items]
Gross investment income	$ 217	$ 228	$ 662	$ 730
Less: investment expenses	5	6	15	18
Total	212	222	647	712
Fixed maturities [Member]
Net Investment Income [Line Items]
Gross investment income	191	205	585	644
Mortgage loans [Member]
Net Investment Income [Line Items]
Gross investment income	29	29	86	88
Other investments [Member]
Net Investment Income [Line Items]
Gross investment income	$ 3	$ 6	$ 9	$ 2

Amount, before 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.

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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.

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