Investment Holding Level 4 Investment Income (Details) - USD ($) $ in Millions	5 Months Ended	7 Months Ended	12 Months Ended
May 31, 2018	Dec. 31, 2018	Dec. 31, 2019	Dec. 31, 2017
Net Investment Income [Line Items]
Investment Income, Investment Expense	$ (19)	$ (18)	$ (24)	$ (55)
Net Investment Income	520	509	924	1,281
Fixed Maturities [Member]
Net Investment Income [Line Items]
Gross Investment Income, Operating	395	343	586	995
Equity Securities [Member]
Net Investment Income [Line Items]
Gross Investment Income, Operating	4	9	6	9
Mortgages [Member]
Net Investment Income [Line Items]
Gross Investment Income, Operating	54	49	92	124
Policy Loans [Member]
Net Investment Income [Line Items]
Gross Investment Income, Operating	32	48	84	79
Limited Partnerships and Other Alternative Investments [Member]
Net Investment Income [Line Items]
Gross Investment Income, Operating	41	67	161	75
Other Investments [Member]
Net Investment Income [Line Items]
Gross Investment Income, Operating	$ 13	$ 11	$ 19	$ 54

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.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-SubTopic 220
-Section S99
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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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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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