v3.2.0.727

Segment Information (Net Premiums Earned For Segment By Product) (Detail) - USD ($) $ in Millions | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2015 | Jun. 30, 2014 | Jun. 30, 2015 | Jun. 30, 2014
Segment Reporting Information [Line Items] |  |  |  |
Property & All Other | $ 1,659 | $ 1,612 | $ 2,978 | $ 2,967
Casualty | 1,588 | 1,542 | 3,094 | 3,022
Life, Accident & Health | 1,113 | 1,178 | 2,215 | 2,313
Net premiums earned | 4,360 | 4,332 | 8,287 | 8,302
Insurance - North American P&C [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Net premiums earned | 1,688 | 1,542 | 3,214 | 3,029
Insurance - North American P&C [Member] | Property Insurance Product Line [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Net premiums earned | 507 | 423 | 917 | 828
Insurance - North American P&C [Member] | Casualty Insurance Product Line [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Net premiums earned | 1,079 | 1,018 | 2,094 | 1,999
Insurance - North American P&C [Member] | Life Accident And Health Product Line [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Net premiums earned | 102 | 101 | 203 | 202
Insurance - North American Agriculture [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Net premiums earned | 321 | 330 | 385 | 433
Insurance - North American Agriculture [Member] | Property Insurance Product Line [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Net premiums earned | 321 | 330 | 385 | 433
Insurance - North American Agriculture [Member] | Casualty Insurance Product Line [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Net premiums earned | 0 | 0 | 0 | 0
Insurance - North American Agriculture [Member] | Life Accident And Health Product Line [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Net premiums earned | 0 | 0 | 0 | 0
Insurance - Overseas General [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Net premiums earned | 1,644 | 1,709 | 3,281 | 3,321
Insurance - Overseas General [Member] | Property Insurance Product Line [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Net premiums earned | 729 | 727 | 1,457 | 1,420
Insurance - Overseas General [Member] | Casualty Insurance Product Line [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Net premiums earned | 391 | 395 | 773 | 764
Insurance - Overseas General [Member] | Life Accident And Health Product Line [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Net premiums earned | 524 | 587 | 1,051 | 1,137
Global Reinsurance [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Net premiums earned | 220 | 261 | 446 | 545
Global Reinsurance [Member] | Property Insurance Product Line [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Net premiums earned | 102 | 132 | 219 | 286
Global Reinsurance [Member] | Casualty Insurance Product Line [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Net premiums earned | 118 | 129 | 227 | 259
Global Reinsurance [Member] | Life Accident And Health Product Line [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Net premiums earned | 0 | 0 | 0 | 0
Life [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Net premiums earned | 487 | 490 | 961 | 974
Life [Member] | Property Insurance Product Line [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Net premiums earned | 0 | 0 | 0 | 0
Life [Member] | Casualty Insurance Product Line [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Net premiums earned | 0 | 0 | 0 | 0
Life [Member] | Life Accident And Health Product Line [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Net premiums earned | $ 487 | $ 490 | $ 961 | $ 974

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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 "Casualty". + 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 "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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- 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 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 2: 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 3: 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 Reference 4: 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 + Details
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