Investments (Net Inv Inc summary) (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 [Line Items]
Gross investment income	$ 216	$ 240	$ 445	$ 502
Less: investment expenses	4	6	10	12
Total	212	234	435	490
Fixed maturities [Member]
Net Investment Income [Line Items]
Gross investment income	193	210	394	439
Mortgage loans [Member]
Net Investment Income [Line Items]
Gross investment income	28	30	57	59
Other investments [Member]
Net Investment Income [Line Items]
Gross investment income	$ (5)	$ 0	$ (6)	$ 4

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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