Transactions With Affiliates (Balance Sheet Transactions With Affiliates) (Details) - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017
Related Party Transaction [Line Items]
Assets	$ 299,145	$ 281,872
Liabilities	282,826	263,427
Accrued Inter-Company Interest [Member] | Accrued Investment Income [Member]
Related Party Transaction [Line Items]
Assets	11	8
Accrued Inter-Company Interest [Member] | Other Liabilities [Member]
Related Party Transaction [Line Items]
Liabilities	13	29
Limited Partnerships [Member] | Other Investments [Member]
Related Party Transaction [Line Items]
Assets		(66)
Ceded Reinsurance Contracts [Member] | Deferred Acquisition Costs And Value Of Business Acquired [Member]
Related Party Transaction [Line Items]
Assets	(188)	(188)
Ceded Reinsurance Contracts [Member] | Reinsurance Recoverables [Member]
Related Party Transaction [Line Items]
Assets	2,574	2,152
Ceded Reinsurance Contracts [Member] | Reinsurance Related Embedded Derivatives [Member]
Related Party Transaction [Line Items]
Assets	191	8
Ceded Reinsurance Contracts [Member] | Other Assets [Member]
Related Party Transaction [Line Items]
Assets	235	244
Ceded Reinsurance Contracts [Member] | Other Liabilities [Member]
Related Party Transaction [Line Items]
Liabilities	325	1,023
Ceded Reinsurance Contracts [Member] | Other Contract Holder Funds [Member]
Related Party Transaction [Line Items]
Liabilities	(46)	(47)
Ceded Reinsurance Contracts [Member] | Funds Withheld Reinsurance Liabilities [Member]
Related Party Transaction [Line Items]
Liabilities	3,120	2,587
Cash Management Agreement [Member] | Other Assets [Member]
Related Party Transaction [Line Items]
Assets	112	441
Service Agreement [Member] | Other Assets [Member]
Related Party Transaction [Line Items]
Assets	5	15
Service Agreement [Member] | Other Liabilities [Member]
Related Party Transaction [Line Items]
Liabilities	56	8
Assumed Reinsurance Contracts [Member] | Future Contract Benefits [Member]
Related Party Transaction [Line Items]
Liabilities	29	32
Assumed Reinsurance Contracts [Member] | Other Contract Holder Funds [Member]
Related Party Transaction [Line Items]
Liabilities	400	400
Inter-Company Debt [Member] | Fixed Maturity Securities [Member]
Related Party Transaction [Line Items]
Assets	1,512	1,444
Inter-Company Debt [Member] | Short-term Debt [Member]
Related Party Transaction [Line Items]
Liabilities	288	10
Inter-Company Debt [Member] | Long-term Debt [Member]
Related Party Transaction [Line Items]
Liabilities	$ 2,401	$ 2,374