Investments (Schedule Of Investments In Partially-Owned Insurance Companies) (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Investment [Line Items]
Carrying Value	$ 504	$ 470
Issued Share Capital	1,112	1,046
Freisenbruch-Meyer \| Bermuda
Investment [Line Items]
Carrying Value	9	9
Issued Share Capital	5	5
Ownership Percentage	40.00%	40.00%
ACE Cooperative Ins. Co. - Saudi Arabia \| Saudi Arabia
Investment [Line Items]
Carrying Value	10	10
Issued Share Capital	27	27
Ownership Percentage	30.00%	30.00%
Huatai Group \| China
Investment [Line Items]
Carrying Value	397	365
Issued Share Capital	638	631
Ownership Percentage	20.00%	20.00%
Huatai Life Insurance Company \| China
Investment [Line Items]
Carrying Value	86	84
Issued Share Capital	438	379
Ownership Percentage	20.00%	20.00%
Russian Reinsurance Company \| Russia
Investment [Line Items]
Carrying Value	2	2
Issued Share Capital	$ 4	$ 4
Ownership Percentage	23.30%	23.30%

Investments in affiliates subsidiaries associates and joint ventures issued share capital.

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- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 323

-SubTopic 10

-Section 50

-Paragraph 3

-Subparagraph (a)(1)

-URI http://asc.fasb.org/extlink&oid=6382943&loc=d3e33918-111571

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- Definition

Total investments in (A) an entity in which the entity has significant influence, but does not have control, (B) subsidiaries that are not required to be consolidated and are accounted for using the equity and or cost method, and (C) an entity in which the reporting entity shares control of the entity with another party or group. Includes long-term advances receivable from a party that is affiliated with the reporting entity by means of direct or indirect ownership.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.12)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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