Investments (Schedule Of Other Investments) (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Schedule of Cost-method Investments [Line Items]
Other investments - Total at Fair Value	$ 3,346us-gaap_OtherLongTermInvestments	$ 2,976us-gaap_OtherLongTermInvestments
Other investments - Total at Cost	2,999	2,671
Fair Value
Schedule of Cost-method Investments [Line Items]
Investment funds	378	428
Limited partnerships	691	576
Partially owned investment companies	1,492	1,284
Life insurance policies	205	180
Policy loans	187	179
Trading securities	290	276
Other	103	53
Other investments - Total at Fair Value	3,346	2,976
Cost
Schedule of Cost-method Investments [Line Items]
Investment funds	228	278
Limited partnerships	497	424
Partially owned investment companies	1,492	1,284
Life insurance policies	205	180
Policy loans	187	179
Trading securities	287	273
Other	103	53
Other investments - Total at Cost	$ 2,999	$ 2,671

Investment funds.

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- Definition

Total of alternative investments.

+ References

No definition available.

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- Definition

Limited partnerships.

+ References

No definition available.

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- Definition

Other Other Investments

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No definition available.

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- Definition

Policy loans investments.

+ References

No definition available.

+ Details

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- Definition

Face value (death benefits) of the life insurance policies underlying the life settlement contracts accounted for under the fair value method.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Life Settlement Contract

-URI http://asc.fasb.org/extlink&oid=6516907

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 325

-SubTopic 30

-Section 50

-Paragraph 8

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=6385267&loc=d3e42732-111610

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- Definition

Includes other investments and securities that are not at fair value as of the balance sheet date and those that are not accounted for under the equity method.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.7-03.1)

-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph a

-Subparagraph 1(g)

-Article 7

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- Definition

Other long-term investments not otherwise specified in the taxonomy, not including investments in marketable securities.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

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-Subparagraph (SX 210.5-02.12)

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-Number 210

-Section 02

-Paragraph 12

-Article 5

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-Number 210

-Section 03

-Paragraph 1

-Subparagraph f

-Article 7

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- Definition

Amount of investments in debt and equity securities and other forms of securities that provide ownership interests classified as trading.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6871852&loc=d3e26610-111562

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-URI http://asc.fasb.org/extlink&oid=6871852&loc=d3e26626-111562

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-Publisher FASB

-Name Accounting Standards Codification

-Glossary Trading Securities

-URI http://asc.fasb.org/extlink&oid=6526789

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.4)

-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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