v2.4.0.8

Segment Information (Net Premiums Earned For Segment By Product) (Detail) (USD $) In Millions, unless otherwise specified | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2014 | Sep. 30, 2013 | Sep. 30, 2014 | Sep. 30, 2013
Segment Reporting Information [Line Items] |  |  |  |
Property & All Other | $ 2,079 | $ 2,067 | $ 5,046 | $ 4,695
Casualty | 1,493 | 1,430 | 4,515 | 4,237
Life, Accident & Health | 1,182 | 1,113 | 3,495 | 3,318
Net premiums earned | 4,754 | 4,610 | 13,056 | 12,250
Insurance - North American P&C [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Property & All Other | 420 | 388 | 1,248 | 1,103
Casualty | 993 | 957 | 2,992 | 2,826
Life, Accident & Health | 105 | 99 | 307 | 281
Net premiums earned | 1,518 | 1,444 | 4,547 | 4,210
Insurance - North American Agriculture [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Property & All Other | 766 | 849 | 1,199 | 1,252
Casualty | 0 | 0 | 0 | 0
Life, Accident & Health | 0 | 0 | 0 | 0
Net premiums earned | 766 | 849 | 1,199 | 1,252
Insurance - Overseas General [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Property & All Other | 744 | 689 | 2,164 | 1,932
Casualty | 394 | 375 | 1,158 | 1,088
Life, Accident & Health | 588 | 547 | 1,725 | 1,613
Net premiums earned | 1,726 | 1,611 | 5,047 | 4,633
Global Reinsurance [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Property & All Other | 149 | 141 | 435 | 408
Casualty | 106 | 98 | 365 | 323
Net premiums earned | 255 | 239 | 800 | 731
Life [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Life, Accident & Health | 489 | 467 | 1,463 | 1,424
Net premiums earned | $ 489 | $ 467 | $ 1,463 | $ 1,424

X
- Definition Premiums earned on the income statement for all insurance and reinsurance contracts after subtracting any amounts ceded to another insurer and adding premiums assumed from other insurers as it relates to the product line of "Casualty". + References No definition available. + Details
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X
- Definition Premiums earned on the income statement for all insurance and reinsurance contracts after subtracting any amounts ceded to another insurer and adding premiums assumed from other insurers as it relates to the product line of "Life, Accident & Health". + References No definition available. + Details
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- Definition Premiums earned on the income statement for all insurance and reinsurance contracts after subtracting any amounts ceded to another insurer and adding premiums assumed from other insurers as it relates to the product line of "Property and All Other". + References No definition available. + Details
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Namespace Prefix: | ace_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Amount, after premiums ceded to other entities and premiums assumed by the entity, of premiums earned. + References 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 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 225 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-04.1) -URI http://asc.fasb.org/extlink&oid=6879464&loc=d3e573970-122913 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Paragraph 1 -Article 7 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 605 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6486672&loc=d3e27261-158547 Reference 6: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 225 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-04.13(c)) -URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882 + Details
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- Details
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