Variable Interest Entities - Carrying Value and Exposure of Non-Consolidated VIEs (Details) - Variable Interest Entity, Not Primary Beneficiary - USD ($) $ in Millions	Dec. 31, 2016	Dec. 31, 2015
Variable Interest Entity [Line Items]
Carrying Value	$ 22,161	$ 20,462
Maximum Loss Exposure	22,730	21,590
Consolidated Entity Excluding Variable Interest Entities (VIE) and Related Party \| Total fixed maturity securities
Variable Interest Entity [Line Items]
Carrying Value	19,171	17,673
Maximum Loss Exposure	19,090	18,146
Consolidated Entity Excluding Variable Interest Entities (VIE) \| Related Party \| Total fixed maturity securities
Variable Interest Entity [Line Items]
Carrying Value	530	525
Maximum Loss Exposure	536	554
Investment funds \| Consolidated Entity Excluding Variable Interest Entities (VIE) and Related Party
Variable Interest Entity [Line Items]
Carrying Value	689	733
Maximum Loss Exposure	1,026	878
Investment funds \| Consolidated Entity Excluding Variable Interest Entities (VIE) \| Related Party
Variable Interest Entity [Line Items]
Carrying Value	1,198	997
Maximum Loss Exposure	1,485	1,454
Investment funds \| Variable Interest Entities
Variable Interest Entity [Line Items]
Carrying Value	573	534
Maximum Loss Exposure	$ 593	$ 558

The reporting entity's maximum amount of exposure to loss as a result of its involvement with the Variable Interest Entity (VIE).

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph b
-URI http://asc.fasb.org/extlink&oid=64801991&loc=d3e5728-111685

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 50
-Paragraph 6
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=64801991&loc=d3e5747-111685

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

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.

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Carrying amount of the assets in the reporting entity's statement of financial position that relate to the reporting entity's variable interest in the Variable Interest Entity (VIE), where the reporting entity is not the VIE's primary beneficiary.

+ References

+ Details

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Balance Type:	debit
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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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