Reinsurance (Effect of Reinsurance on Life Insurance In Force) (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Reinsurance Disclosures [Abstract]
Reinsurance Premiums for Insurance Companies, by Product Segment, Gross Amount	$ 78us-gaap_LifeInsuranceInForceGross	$ 77us-gaap_LifeInsuranceInForceGross	$ 76us-gaap_LifeInsuranceInForceGross
Reinsurance Premiums for Insurance Companies, by Product Segment, Amount Assumed from Other Companies	2,943,517us-gaap_LifeInsuranceInForceAssumed	2,889,804us-gaap_LifeInsuranceInForceAssumed	2,927,573us-gaap_LifeInsuranceInForceAssumed
Reinsurance Premiums for Insurance Companies, by Product Segment, Amount Ceded to Other Companies	230,544us-gaap_LifeInsuranceInForceCeded	36,830us-gaap_LifeInsuranceInForceCeded	38,048us-gaap_LifeInsuranceInForceCeded
Reinsurance Premiums for Insurance Companies, by Product Segment, Net Amount	$ 2,713,051us-gaap_LifeInsuranceInForceNet	$ 2,853,051us-gaap_LifeInsuranceInForceNet	$ 2,889,601us-gaap_LifeInsuranceInForceNet
Reinsurance Premiums for Insurance Companies, by Product Segment, Percentage of Amount Assumed to Net	108.50%	101.30%	101.30%

Amount of life insurance issued and outstanding assumed from other entities. Includes, but not limited to, dividends and adjustments to face value.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 17

-Article 12

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 235

-Section S99

-Paragraph 2

-Subparagraph (SX 210.12-17)

-URI http://asc.fasb.org/extlink&oid=34713774&loc=d3e574992-122915

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- Definition

Amount of life insurance issued and outstanding ceded to other entities. Includes, but not limited to, dividends and adjustments to face value.

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- Definition

Amount before contracts ceded to other entities and contracts assumed by the entity of life insurance issued and outstanding. Includes, but not limited to, dividends and adjustments to face value.

+ References

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- Definition

Amount after contracts ceded to other entities and contracts assumed by the entity of life insurance issued and outstanding. Includes, but not limited to, dividends and adjustments to face value.

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- Definition

Percentage of assumed life insurance issued and outstanding contracts to life insurance issued and outstanding after contracts ceded to other entities and contracts assumed by the entity. Includes, but not limited to, dividends and adjustments to face value.

+ References

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