XML 78 R67.htm IDEA: XBRL DOCUMENT
v3.10.0.1

Segment information Segment Information (narrative Detail (Details) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2018 | Sep. 30, 2017 | Sep. 30, 2018 | Sep. 30, 2017
Segment Reporting Information [Line Items] |  |  |  |
Gain (Loss) on Derivative | $ (17) | $ (22) | $ 91 | $ 68
Net investment income | 823 | 813 | 2,457 | 2,328
North America Agricultural Insurance [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Segment Income Loss Including Gains Losses On Crop Derivatives | 79 |  |  |
Gain (Loss) on Derivative | (8) |  |  |
Net investment income | 7 | 6 | 20 | 18
Segment Life [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Net investment income | 85 | $ 78 | $ 253 | $ 230
Management Underwriting Income (Loss) | 84 |  |  |
Gains(Losses) On Fair Value Changes In Separate Account Assets | $ (14) |  |  |

X
- Definition Gains Losses On Fair Value Changes In Separate Account Assets + References No definition available. + Details
Name: | cb_GainsLossesOnFairValueChangesInSeparateAccountAssets
Namespace Prefix: | cb_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Management Underwriting Income Loss Insurance + References No definition available. + Details
Name: | cb_ManagementUnderwritingIncomeLossInsurance
Namespace Prefix: | cb_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Segment Income Loss Including Gains Losses On Crop Derivatives + References No definition available. + Details
Name: | cb_SegmentIncomeLossIncludingGainsLossesOnCropDerivatives
Namespace Prefix: | cb_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Amount of increase (decrease) in the fair value of derivatives recognized in the income statement. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4A -Subparagraph (b)(1) -URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5618551-113959 + Details
Name: | us-gaap_DerivativeGainLossOnDerivativeNet
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Amount, after investment expense, of income earned from investments in securities and real estate. Includes, but is not limited to, real estate investment, policy loans, dividends, and interest. Excludes realized gain (loss) on investments. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 220 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-04(2)) -URI http://asc.fasb.org/extlink&oid=114873790&loc=SL114874131-224263 + Details
Name: | us-gaap_NetInvestmentIncome
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
Name: | us-gaap_SegmentReportingInformationLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | us-gaap_StatementBusinessSegmentsAxis=cb_SegmentInsuranceNorthAmericanAgricultureMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_StatementBusinessSegmentsAxis=cb_SegmentLifeMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |