Transactions With Affiliates (Comprehensive Income (Loss) Transactions With Affiliates) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Related Party Transaction [Line Items]
Insurance premiums	$ 4,362	$ 3,018	$ 2,579
Net investment income	4,844	4,760	4,631
Realized gain (loss)	(92)	(456)	(510)
Amortization of deferred gain on business sold through reinsurance	4	18	69
Interest credited	2,589	2,558	2,527
Benefits	6,144	4,818	4,247
Commissions and other expenses	4,583	3,967	4,005
Interest and debt expense	136	126	116
Premiums Received On Assumed (Paid On Ceded) Reinsurance Contract [Member]
Related Party Transaction [Line Items]
Insurance premiums	(404)	(393)	(389)
Fees For Management Of General Account [Member]
Related Party Transaction [Line Items]
Net investment income	(106)	(100)	(117)
Ceded Funds Withheld Treaties [Member]
Related Party Transaction [Line Items]
Net investment income	(123)	(84)	(69)
Ceded Reinsurance Contracts [Member]
Related Party Transaction [Line Items]
Benefits	(610)	(299)	(424)
Commissions and other expenses	(8)	(12)	(14)
Ceded Reinsurance Contracts [Member] \| GLB Reserves Embedded Derivative [Member]
Related Party Transaction [Line Items]
Realized gain (loss)	709	(1,055)	(516)
Ceded Reinsurance Contracts [Member] \| Reinsurance Related Embedded Derivatives [Member]
Related Party Transaction [Line Items]
Realized gain (loss)	(1,189)	951	488
Ceded Reinsurance Contracts [Member] \| Other Gains (Losses) [Member]
Related Party Transaction [Line Items]
Realized gain (loss)	237	(150)	(93)
Service Agreement [Member]
Related Party Transaction [Line Items]
Commissions and other expenses	3	3	76
Assumed Reinsurance Contracts [Member]
Related Party Transaction [Line Items]
Interest credited	57	67	61
Inter-Company Debt [Member]
Related Party Transaction [Line Items]
Net investment income	49	42	38
Interest and debt expense	126	120	111
Amortization Of Deferred Gain On Business Sold Through Reinsurance, Pre-Tax [Member]
Related Party Transaction [Line Items]
Amortization of deferred gain on business sold through reinsurance	$ (5)	$ (5)	$ (5)

The amortization of net deferred gain (loss) on indemnity reinsurance transactions.

No definition available.

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This item represents the net total realized and unrealized gain (loss) included in earnings for the period as a result of selling or holding marketable securities categorized as trading, available-for-sale, or held-to-maturity, including the unrealized holding gain (loss) of held-to-maturity securities transferred to the trading security category and the cumulative unrealized gain (loss) which was included in other comprehensive income (a separate component of shareholders' equity) for available-for-sale securities transferred to trading securities during the period. Additionally, this item would include any gains (losses) realized during the period from the sale of investments accounted for under the cost method of accounting, losses recognized for other than temporary impairments (OTTI) of the subject investments, derivatives and embedded derivatives gains and losses and gains and losses from reinsurance embedded derivatives.

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Interest allocated to policyholders holding contracts under which the insurer must provide a guaranteed yield.

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Amount of the cost of borrowed funds accounted for as interest expense for debt.

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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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The total amount of other operating cost and expense items that are associated with the entity's normal revenue producing operation.

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Amount, after effects of policies assumed or ceded, of expense related to the provision for policy benefits and costs incurred.

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Amount, after premiums ceded to other entities and premiums assumed by the entity, of premiums earned.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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