DAC, VOBA, DSI, and DFEL (DAC) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Changes in DAC [Roll Forward]
Balance as of beginning-of-year	$ 5,590	$ 7,418	$ 9,509
Business acquired (sold) through reinsurance	(362)	(26)
Business recaptured through reinsurance			59
Deferrals	1,364	1,427	1,900
Amortization, net of interest:
Amortization, excluding unlocking, net of interest	(980)	(811)	(922)
Unlocking	(558)	(211)	(471)
Adjustment related to realized gains (losses)	(45)	(35)	(43)
Adjustment related to unrealized (gains) losses	792	(2,177)	(2,614)
Balance as of end-of-year	$ 5,801	5,590	7,418
Cumulative Effect, Period of Adoption, Adjustment [Member]
Changes in DAC [Roll Forward]
Balance as of beginning-of-year		$ 5
Amortization, net of interest:
Balance as of end-of-year			$ 5

The amount of other amortization of deferred policy acquisition costs, net of interest, during the period.

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- Definition

Additions in deferred policy acquisition costs during the year arising from acquisitions of insurance entities.

+ References

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Deferred policy acquisition costs, Business recaptured through reinsurance

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Amount of amortization expense (reversal of amortization expense) of deferred policy acquisition costs from a revision in estimated gross profit or estimated gross margin.

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Amount of amortization expense (reversal of amortization expense) of deferred policy acquisition costs from realized net investment gain (loss).

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Amount of unrealized investment gain (loss) which decreases (increases) deferred policy acquisition cost.

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Amount of deferred policy acquisition cost capitalized on contract remaining in force.

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Amount of deferred policy acquisition cost capitalized.

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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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