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, 2017	Dec. 31, 2016
Net Investment Income [Line Items]
Investment Income, Investment Expense	$ (19)	$ (18)	$ (55)	$ (52)
Net Investment Income	520	509	1,281	1,373
Fixed Maturities [Member]
Net Investment Income [Line Items]
Gross Investment Income, Operating	395	343	995	1,049
Equity Securities [Member]
Net Investment Income [Line Items]
Gross Investment Income, Operating	4	9	9	8
Mortgages [Member]
Net Investment Income [Line Items]
Gross Investment Income, Operating	54	49	124	135
Policy Loans [Member]
Net Investment Income [Line Items]
Gross Investment Income, Operating	32	48	79	83
Limited Partnerships and Other Alternative Investments [Member]
Net Investment Income [Line Items]
Gross Investment Income, Operating	41	67	75	86
Limited Partnerhips Accounted for using Equity Method				96
Other Investments [Member]
Net Investment Income [Line Items]
Gross Investment Income, Operating	$ 13	$ 11	$ 54	$ 64

Limited Partnerhips Accounted for using Equity Method

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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.

+ References

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-Topic 944
-SubTopic 220
-Section S99
-Paragraph 1
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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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