Investments - Unrealized Net Capital Gains and Losses (Details) - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018
Fair value
Fixed income securities	$ 21,541	$ 21,400
Short-term investments	1,284	810
Gross unrealized Gains
Fixed income securities	1,006	732
Short-term investments	0	0
Gross unrealized Losses
Fixed income securities	(129)	(389)
Short-term investments	0	0
Unrealized net gains (losses)
Fixed income securities	877	343
Short-term investments		0
Unrealized net capital gains and losses, pre-tax	877	343
Amount recognized for:
Insurance reserves	(8)	0
DAC and DSI	(123)	(35)
Amounts recognized	(131)	(35)
Deferred income taxes	(157)	(65)
Total unrealized net capital gains and losses	$ 589	$ 243

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Represents the unrealized gains included in accumulated other comprehensive income as of the balance sheet date, for the fixed income securities which are categorized neither as held-to-maturity nor trading securities.

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The amount of unrealized gains (losses) included in accumulated other comprehensive income on fixed income securities which are categorized neither as held-to-maturity nor trading securities, as a result of fair value exceeding (under) its amortized cost, as of the balance sheet date.

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Available for sale Short-term Investments, Unrealized Gain Included in Other Comprehensive Income

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Accumulated adjustment to deferred income taxes related to unrealized capital gains and losses, as of the balance sheet date.

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Accumulated adjustment to Deferred Policy Acquisition Costs, Deferred Sales Inducement Costs, and insurance reserves related to unrealized capital gains and losses, before tax, at the end of an accounting period.

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Deferred Policy Acquisition Costs and Deferred Sales Inducement Costs adjustment included in accumulated other comprehensive income (loss) which represents the amount by which the amortization of DAC and DSI would increase or decrease if the unrealized gains or losses in the respective product portfolios were realized.

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Insurance reserve adjustment included in accumulated other comprehensive income (loss) which represents the amount by which the reserve balance would increase if the net unrealized gains in the applicable product portfolios were realized and reinvested at current lower interest rates, resulting in a premium deficiency.

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The amount of unrealized gain (loss) before taxes on all investment securities, which are included in accumulated other comprehensive income (loss), as a result of fair value exceeding (under) its cost, as of the balance sheet date.

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Accumulated unrealized gain (loss), after tax, on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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