XML 64 R53.htm IDEA: XBRL DOCUMENT
v3.21.1

RESERVE FOR LOSSES AND LOSS EXPENSES - Prior year reserve development by segment, reserving class and accident year (Details) - USD ($) $ in Thousands | 3 Months Ended
--- | ---
Mar. 31, 2021 | Mar. 31, 2020
Liability for Future Policy Benefit, by Product Segment [Line Items] |  |
Prior years | $ 5,317 | $ 6,113
Insurance |  |
Liability for Future Policy Benefit, by Product Segment [Line Items] |  |
Prior years | 1,505 | 3,832
Insurance | Property and other |  |
Liability for Future Policy Benefit, by Product Segment [Line Items] |  |
Prior years | 15,391 | 12,491
Insurance | Marine |  |
Liability for Future Policy Benefit, by Product Segment [Line Items] |  |
Prior years | 11,875 | (2,202)
Insurance | Aviation |  |
Liability for Future Policy Benefit, by Product Segment [Line Items] |  |
Prior years | 1,035 | 3,991
Insurance | Credit and political risk |  |
Liability for Future Policy Benefit, by Product Segment [Line Items] |  |
Prior years | (5,371) | (916)
Insurance | Professional lines |  |
Liability for Future Policy Benefit, by Product Segment [Line Items] |  |
Prior years | (14,593) | (5,087)
Insurance | Liability |  |
Liability for Future Policy Benefit, by Product Segment [Line Items] |  |
Prior years | (6,832) | (4,445)
Reinsurance |  |
Liability for Future Policy Benefit, by Product Segment [Line Items] |  |
Prior years | 3,812 | 2,281
Reinsurance | Property and other |  |
Liability for Future Policy Benefit, by Product Segment [Line Items] |  |
Prior years | 969 | (3,905)
Reinsurance | Professional lines |  |
Liability for Future Policy Benefit, by Product Segment [Line Items] |  |
Prior years | (2,204) | 5,162
Reinsurance | Liability |  |
Liability for Future Policy Benefit, by Product Segment [Line Items] |  |
Prior years | (7,154) | (16,915)
Reinsurance | Credit and surety |  |
Liability for Future Policy Benefit, by Product Segment [Line Items] |  |
Prior years | (4,939) | 4,854
Reinsurance | Motor |  |
Liability for Future Policy Benefit, by Product Segment [Line Items] |  |
Prior years | $ 17,140 | $ 13,085

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_LiabilityForFuturePolicyBenefitByProductSegmentLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount, after effects of reinsurance, of expense (reversal of expense) for claims incurred in prior reporting periods and related claims settlement costs. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 50 -Paragraph 3 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=116884095&loc=d3e14764-158437 + Details
Name: | us-gaap_SupplementalInformationForPropertyCasualtyInsuranceUnderwritersPriorYearClaimsAndClaimsAdjustmentExpense
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

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

X
- Details
Name: | srt_ProductOrServiceAxis=axs_PropertyandOtherReserveClassMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_ProductOrServiceAxis=axs_MarineMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_ProductOrServiceAxis=axs_AviationMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_ProductOrServiceAxis=axs_CreditAndPoliticalRiskMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_ProductOrServiceAxis=axs_ProfessionalLinesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_ProductOrServiceAxis=axs_LiabilityLineMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

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

X
- Details
Name: | srt_ProductOrServiceAxis=axs_CreditandSuretyBusinessMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_ProductOrServiceAxis=axs_MotorMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |