Closed Block (Information Regarding Policyholder Dividend Obligation) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Movement in Closed Block Dividend Obligation [Roll Forward]
Balance, January 1	$ 3,150	$ 5,446
Impact from earnings allocable to policyholder dividend obligation	564	(508)
Change in net unrealized investment gains (losses) allocated to policyholder dividend obligation	2,435	(1,945)
Balance, December 31	6,149	3,150
ASU 2016-01
Movement in Closed Block Dividend Obligation [Roll Forward]
Cumulative-effect adjustment from the adoption of ASU 2016-01	$ 0	$ 157

Amount of increase (decrease) in the closed block dividend obligation from the unrealized gain (loss) on investments allocated to the closed block.

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-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Amount of increase (decrease) in the closed block dividend obligation from the effect on dividends to policyholders on the net results of operations for the period of the closed block.

+ References

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- Definition

Amount of increase (decrease) in the policyholder dividend obligation attributable to closed block liabilities.

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The liability as of the balance sheet date for the excess of the cumulative actual closed block earnings over the cumulative expected (actuarially determined) closed block earnings (each) for the period from the actuarial calculation date to the date of measurement. The excess will result in future dividends to closed block policyholders, unless offset by less favorable than expected future performance of the closed block. The policyholder dividend obligation, which may not have a negative balance, recognizes that a portion of earnings in certain cases will not inure to the stockholders of the insurance entity.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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