Transactions With Affiliates (Comprehensive Income (Loss) Transactions With Affiliates) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Related Party Transaction [Line Items]
Insurance premiums	$ 5,277	$ 4,362	$ 3,018
Net investment income	4,962	4,844	4,760
Realized gains (losses)	(828)	(92)	(456)
Amortization of deferred gain on business sold through reinsurance	27	4	18
Interest credited	2,754	2,589	2,558
Benefits	7,585	6,144	4,818
Commissions and other expenses	5,065	4,583	3,967
Interest and debt expense	145	136	126
Premiums Received On Assumed (Paid On Ceded) Reinsurance Contract [Member]
Related Party Transaction [Line Items]
Insurance premiums	(407)	(404)	(393)
Fees For Management Of General Account [Member]
Related Party Transaction [Line Items]
Net investment income	(133)	(106)	(100)
Ceded Funds Withheld Treaties [Member]
Related Party Transaction [Line Items]
Net investment income	(139)	(123)	(84)
Ceded Reinsurance Contracts [Member]
Related Party Transaction [Line Items]
Benefits	(254)	(610)	(299)
Commissions and other expenses	(19)	(8)	(12)
Ceded Reinsurance Contracts [Member] \| GLB Reserves Embedded Derivative [Member]
Related Party Transaction [Line Items]
Realized gains (losses)	(305)	709	(1,055)
Ceded Reinsurance Contracts [Member] \| Reinsurance Related Embedded Derivatives [Member]
Related Party Transaction [Line Items]
Realized gains (losses)	472	(1,189)	951
Ceded Reinsurance Contracts [Member] \| Other Gains (Losses) [Member]
Related Party Transaction [Line Items]
Realized gains (losses)	(301)	237	(150)
Service Agreement [Member]
Related Party Transaction [Line Items]
Commissions and other expenses	15	3	3
Assumed Reinsurance Contracts [Member]
Related Party Transaction [Line Items]
Interest credited	60	57	67
Inter-Company Debt [Member]
Related Party Transaction [Line Items]
Net investment income	53	49	42
Interest and debt expense	130	126	120
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	$ (4)	$ (5)	$ (5)

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

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Amount of realized gain (loss) on investment in debt and equity securities.

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Amount of interest expense for allocation to policyholder account balance.

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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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