Derivatives (Embedded Derivatives) (Details) - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018
Derivatives, Fair Value [Line Items]
Embedded derivatives within liability host contracts	$ 674	$ 810
Ceded guaranteed minimum benefits \| Premiums, reinsurance and other receivables
Derivatives, Fair Value [Line Items]
Embedded derivatives within asset host contracts	69	71
Direct guaranteed minimum benefits \| Policyholder account balances
Derivatives, Fair Value [Line Items]
Embedded derivatives within liability host contracts	182	298
Assumed guaranteed minimum benefits \| Policyholder account balances
Derivatives, Fair Value [Line Items]
Embedded derivatives within liability host contracts	393	495
Funds withheld on ceded reinsurance \| Other liabilities
Derivatives, Fair Value [Line Items]
Embedded derivatives within liability host contracts	4	(41)
Fixed annuities with equity indexed returns \| Policyholder account balances
Derivatives, Fair Value [Line Items]
Embedded derivatives within liability host contracts	$ 95	$ 58

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

+ Details

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- Definition

Fair value as of the balance sheet date of the embedded derivative or group of embedded derivatives classified as an asset.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4B
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5624163-113959

+ Details

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- Definition

Fair value as of the balance sheet date of the embedded derivative or group of embedded derivatives classified as a liability.

+ References

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- Details

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