XML 162 R95.htm IDEA: XBRL DOCUMENT
v3.19.3.a.u2

Reserve for Claims and Claim Expenses (Cumulative Number of Claims Reported) (Details) - Excess of Loss Reinsurance Contracts | Dec. 31, 2019 claim
--- | ---
Accident Year 2010 | Property |
Claims Development [Line Items] |
Cumulative number of reported claims (in claims) | 835
Accident Year 2010 | Casualty and Specialty |
Claims Development [Line Items] |
Cumulative number of reported claims (in claims) | 1,215
Accident Year 2011 | Property |
Claims Development [Line Items] |
Cumulative number of reported claims (in claims) | 1,388
Accident Year 2011 | Casualty and Specialty |
Claims Development [Line Items] |
Cumulative number of reported claims (in claims) | 1,964
Accident Year 2012 | Property |
Claims Development [Line Items] |
Cumulative number of reported claims (in claims) | 922
Accident Year 2012 | Casualty and Specialty |
Claims Development [Line Items] |
Cumulative number of reported claims (in claims) | 2,263
Accident Year 2013 | Property |
Claims Development [Line Items] |
Cumulative number of reported claims (in claims) | 799
Accident Year 2013 | Casualty and Specialty |
Claims Development [Line Items] |
Cumulative number of reported claims (in claims) | 2,712
Accident Year 2014 | Property |
Claims Development [Line Items] |
Cumulative number of reported claims (in claims) | 744
Accident Year 2014 | Casualty and Specialty |
Claims Development [Line Items] |
Cumulative number of reported claims (in claims) | 3,421
Accident Year 2015 | Property |
Claims Development [Line Items] |
Cumulative number of reported claims (in claims) | 758
Accident Year 2015 | Casualty and Specialty |
Claims Development [Line Items] |
Cumulative number of reported claims (in claims) | 3,783
Accident Year 2016 | Property |
Claims Development [Line Items] |
Cumulative number of reported claims (in claims) | 1,089
Accident Year 2016 | Casualty and Specialty |
Claims Development [Line Items] |
Cumulative number of reported claims (in claims) | 4,135
Accident Year 2017 | Property |
Claims Development [Line Items] |
Cumulative number of reported claims (in claims) | 2,215
Accident Year 2017 | Casualty and Specialty |
Claims Development [Line Items] |
Cumulative number of reported claims (in claims) | 3,294
Accident Year 2018 | Property |
Claims Development [Line Items] |
Cumulative number of reported claims (in claims) | 2,050
Accident Year 2018 | Casualty and Specialty |
Claims Development [Line Items] |
Cumulative number of reported claims (in claims) | 2,148
Accident Year 2019 | Property |
Claims Development [Line Items] |
Cumulative number of reported claims (in claims) | 861
Accident Year 2019 | Casualty and Specialty |
Claims Development [Line Items] |
Cumulative number of reported claims (in claims) | 816

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

X
- Definition Cumulative number of reported claims for short-duration insurance contracts. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 50 -Paragraph 4D -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=116884468&loc=SL65671317-158438 + Details
Name: | us-gaap_ShortdurationInsuranceContractsNumberOfReportedClaims
Namespace Prefix: | us-gaap_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | instant

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

X
- Details
Name: | us-gaap_ShortdurationInsuranceContractsAccidentYearAxis=us-gaap_ShortdurationInsuranceContractsAccidentYear2010Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

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

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

X
- Details
Name: | us-gaap_ShortdurationInsuranceContractsAccidentYearAxis=us-gaap_ShortdurationInsuranceContractsAccidentYear2011Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_ShortdurationInsuranceContractsAccidentYearAxis=us-gaap_ShortdurationInsuranceContractsAccidentYear2012Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_ShortdurationInsuranceContractsAccidentYearAxis=us-gaap_ShortdurationInsuranceContractsAccidentYear2013Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_ShortdurationInsuranceContractsAccidentYearAxis=us-gaap_ShortdurationInsuranceContractsAccidentYear2014Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_ShortdurationInsuranceContractsAccidentYearAxis=us-gaap_ShortdurationInsuranceContractsAccidentYear2015Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_ShortdurationInsuranceContractsAccidentYearAxis=us-gaap_ShortdurationInsuranceContractsAccidentYear2016Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_ShortdurationInsuranceContractsAccidentYearAxis=us-gaap_ShortDurationInsuranceContractsAccidentYear2017Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_ShortdurationInsuranceContractsAccidentYearAxis=us-gaap_ShortDurationInsuranceContractsAccidentYear2018Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_ShortdurationInsuranceContractsAccidentYearAxis=us-gaap_ShortDurationInsuranceContractAccidentYear2019Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |