DAC, VOBA, DSI, and DFEL (DAC) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Changes in DAC [Roll Forward]
Balance as of beginning-of-year	$ 7,909	$ 8,269	$ 8,620
Business acquired (sold) through reinsurance	(246)
Deferrals	1,596	1,345	1,339
Amortization, net of interest:
Amortization, excluding unlocking, net of interest	(913)	(922)	(879)
Unlocking	(115)	61	(276)
Adjustment related to realized gains (losses)	(42)	(55)	(51)
Adjustment related to unrealized (gains) losses	1,320	(789)	(484)
Balance as of end-of-year	$ 9,509	$ 7,909	$ 8,269

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

No definition available.

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- Definition

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

+ References

No definition available.

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- References

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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.

+ References

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- Definition

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

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- Definition

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

+ References

No definition available.

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- Definition

Net amount of deferred policy acquisition costs capitalized on contracts remaining in force as of the balance sheet date.

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- Definition

Total amount of policy acquisition costs capitalized during the income statement period.

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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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