XML 48 R53.htm IDEA: XBRL DOCUMENT v2.4.1.9

Fair Value Measurements (Assets and Liabilities Measured at Fair Value on a Recurring Basis) (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity investments	$ 6,007,929us-gaap_MarketableSecuritiesFixedMaturities	$ 4,783,570us-gaap_MarketableSecuritiesFixedMaturities
Short term investments	1,775,819us-gaap_OtherShortTermInvestments	1,013,222us-gaap_OtherShortTermInvestments
Equity investments trading	261,656us-gaap_TradingSecuritiesEquity	322,098us-gaap_TradingSecuritiesEquity
Other investments	514,906us-gaap_OtherInvestments	504,147us-gaap_OtherInvestments
Other assets and (liabilities)	78,822rnr_OtherAssetsAndliabilitiesMeasuredonRecurringBasis	(13,908)rnr_OtherAssetsAndliabilitiesMeasuredonRecurringBasis
Total assets and liabilities measured on recurring basis	8,639,132rnr_TotalAssetsAndLiabilitiesMeasuredAtFairValueOnRecurringBasis	6,609,129rnr_TotalAssetsAndLiabilitiesMeasuredAtFairValueOnRecurringBasis
Quoted Prices In Active Markets For Identical Assets (Level 1)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity investments	1,535,746us-gaap_MarketableSecuritiesFixedMaturities / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member	1,671,471us-gaap_MarketableSecuritiesFixedMaturities / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member
Short term investments	0us-gaap_OtherShortTermInvestments / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member	0us-gaap_OtherShortTermInvestments / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member
Equity investments trading	261,656us-gaap_TradingSecuritiesEquity / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member	322,098us-gaap_TradingSecuritiesEquity / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member
Other investments	0us-gaap_OtherInvestments / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member	0us-gaap_OtherInvestments / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member
Other assets and (liabilities)	(492)rnr_OtherAssetsAndliabilitiesMeasuredonRecurringBasis / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member	(569)rnr_OtherAssetsAndliabilitiesMeasuredonRecurringBasis / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member
Total assets and liabilities measured on recurring basis	1,796,910rnr_TotalAssetsAndLiabilitiesMeasuredAtFairValueOnRecurringBasis / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member	1,993,000rnr_TotalAssetsAndLiabilitiesMeasuredAtFairValueOnRecurringBasis / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member
Significant Other Observable Inputs (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity investments	4,456,709us-gaap_MarketableSecuritiesFixedMaturities / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member	3,096,439us-gaap_MarketableSecuritiesFixedMaturities / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member
Short term investments	1,775,819us-gaap_OtherShortTermInvestments / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member	1,013,222us-gaap_OtherShortTermInvestments / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member
Equity investments trading	0us-gaap_TradingSecuritiesEquity / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member	0us-gaap_TradingSecuritiesEquity / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member
Other investments	221,780us-gaap_OtherInvestments / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member	200,329us-gaap_OtherInvestments / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member
Other assets and (liabilities)	6,345rnr_OtherAssetsAndliabilitiesMeasuredonRecurringBasis / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member	(4,405)rnr_OtherAssetsAndliabilitiesMeasuredonRecurringBasis / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member
Total assets and liabilities measured on recurring basis	6,460,653rnr_TotalAssetsAndLiabilitiesMeasuredAtFairValueOnRecurringBasis / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member	4,305,585rnr_TotalAssetsAndLiabilitiesMeasuredAtFairValueOnRecurringBasis / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member
Significant Unobservable Inputs (Level 3)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity investments	15,474us-gaap_MarketableSecuritiesFixedMaturities / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member	15,660us-gaap_MarketableSecuritiesFixedMaturities / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member
Short term investments	0us-gaap_OtherShortTermInvestments / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member	0us-gaap_OtherShortTermInvestments / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member
Equity investments trading	0us-gaap_TradingSecuritiesEquity / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member	0us-gaap_TradingSecuritiesEquity / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member
Other investments	293,126us-gaap_OtherInvestments / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member	303,818us-gaap_OtherInvestments / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member
Other assets and (liabilities)	72,969rnr_OtherAssetsAndliabilitiesMeasuredonRecurringBasis / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member	(8,934)rnr_OtherAssetsAndliabilitiesMeasuredonRecurringBasis / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member
Total assets and liabilities measured on recurring basis	381,569rnr_TotalAssetsAndLiabilitiesMeasuredAtFairValueOnRecurringBasis / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member	310,544rnr_TotalAssetsAndLiabilitiesMeasuredAtFairValueOnRecurringBasis / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member
U.S. treasuries
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity investments	1,535,746us-gaap_MarketableSecuritiesFixedMaturities / us-gaap_FairValueByAssetClassAxis = us-gaap_USTreasurySecuritiesMember	1,671,471us-gaap_MarketableSecuritiesFixedMaturities / us-gaap_FairValueByAssetClassAxis = us-gaap_USTreasurySecuritiesMember
U.S. treasuries | Quoted Prices In Active Markets For Identical Assets (Level 1)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity investments	1,535,746us-gaap_MarketableSecuritiesFixedMaturities / us-gaap_FairValueByAssetClassAxis = us-gaap_USTreasurySecuritiesMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member	1,671,471us-gaap_MarketableSecuritiesFixedMaturities / us-gaap_FairValueByAssetClassAxis = us-gaap_USTreasurySecuritiesMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member
U.S. treasuries | Significant Other Observable Inputs (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity investments	0us-gaap_MarketableSecuritiesFixedMaturities / us-gaap_FairValueByAssetClassAxis = us-gaap_USTreasurySecuritiesMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member	0us-gaap_MarketableSecuritiesFixedMaturities / us-gaap_FairValueByAssetClassAxis = us-gaap_USTreasurySecuritiesMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member
U.S. treasuries | Significant Unobservable Inputs (Level 3)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity investments	0us-gaap_MarketableSecuritiesFixedMaturities / us-gaap_FairValueByAssetClassAxis = us-gaap_USTreasurySecuritiesMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member	0us-gaap_MarketableSecuritiesFixedMaturities / us-gaap_FairValueByAssetClassAxis = us-gaap_USTreasurySecuritiesMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member
Agencies
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity investments	152,272us-gaap_MarketableSecuritiesFixedMaturities / us-gaap_FairValueByAssetClassAxis = us-gaap_AgencySecuritiesMember	96,208us-gaap_MarketableSecuritiesFixedMaturities / us-gaap_FairValueByAssetClassAxis = us-gaap_AgencySecuritiesMember
Agencies | Quoted Prices In Active Markets For Identical Assets (Level 1)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity investments	0us-gaap_MarketableSecuritiesFixedMaturities / us-gaap_FairValueByAssetClassAxis = us-gaap_AgencySecuritiesMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member	0us-gaap_MarketableSecuritiesFixedMaturities / us-gaap_FairValueByAssetClassAxis = us-gaap_AgencySecuritiesMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member
Agencies | Significant Other Observable Inputs (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity investments	152,272us-gaap_MarketableSecuritiesFixedMaturities / us-gaap_FairValueByAssetClassAxis = us-gaap_AgencySecuritiesMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member	96,208us-gaap_MarketableSecuritiesFixedMaturities / us-gaap_FairValueByAssetClassAxis = us-gaap_AgencySecuritiesMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member
Agencies | Significant Unobservable Inputs (Level 3)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity investments	0us-gaap_MarketableSecuritiesFixedMaturities / us-gaap_FairValueByAssetClassAxis = us-gaap_AgencySecuritiesMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member	0us-gaap_MarketableSecuritiesFixedMaturities / us-gaap_FairValueByAssetClassAxis = us-gaap_AgencySecuritiesMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member
Municipals
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity investments	1,220,206us-gaap_MarketableSecuritiesFixedMaturities / us-gaap_FairValueByAssetClassAxis = us-gaap_USStatesAndPoliticalSubdivisionsMember
Municipals | Quoted Prices In Active Markets For Identical Assets (Level 1)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity investments	0us-gaap_MarketableSecuritiesFixedMaturities / us-gaap_FairValueByAssetClassAxis = us-gaap_USStatesAndPoliticalSubdivisionsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member
Municipals | Significant Other Observable Inputs (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity investments	1,220,206us-gaap_MarketableSecuritiesFixedMaturities / us-gaap_FairValueByAssetClassAxis = us-gaap_USStatesAndPoliticalSubdivisionsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member
Municipals | Significant Unobservable Inputs (Level 3)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity investments	0us-gaap_MarketableSecuritiesFixedMaturities / us-gaap_FairValueByAssetClassAxis = us-gaap_USStatesAndPoliticalSubdivisionsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member
Non-U.S. government (Sovereign Debt)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity investments	329,626us-gaap_MarketableSecuritiesFixedMaturities / us-gaap_FairValueByAssetClassAxis = us-gaap_ForeignGovernmentDebtSecuritiesMember	280,651us-gaap_MarketableSecuritiesFixedMaturities / us-gaap_FairValueByAssetClassAxis = us-gaap_ForeignGovernmentDebtSecuritiesMember
Non-U.S. government (Sovereign Debt) | Quoted Prices In Active Markets For Identical Assets (Level 1)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity investments	0us-gaap_MarketableSecuritiesFixedMaturities / us-gaap_FairValueByAssetClassAxis = us-gaap_ForeignGovernmentDebtSecuritiesMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member	0us-gaap_MarketableSecuritiesFixedMaturities / us-gaap_FairValueByAssetClassAxis = us-gaap_ForeignGovernmentDebtSecuritiesMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member
Non-U.S. government (Sovereign Debt) | Significant Other Observable Inputs (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity investments	329,626us-gaap_MarketableSecuritiesFixedMaturities / us-gaap_FairValueByAssetClassAxis = us-gaap_ForeignGovernmentDebtSecuritiesMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member	280,651us-gaap_MarketableSecuritiesFixedMaturities / us-gaap_FairValueByAssetClassAxis = us-gaap_ForeignGovernmentDebtSecuritiesMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member
Non-U.S. government (Sovereign Debt) | Significant Unobservable Inputs (Level 3)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity investments	0us-gaap_MarketableSecuritiesFixedMaturities / us-gaap_FairValueByAssetClassAxis = us-gaap_ForeignGovernmentDebtSecuritiesMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member	0us-gaap_MarketableSecuritiesFixedMaturities / us-gaap_FairValueByAssetClassAxis = us-gaap_ForeignGovernmentDebtSecuritiesMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member
Non-U.S. government-backed corporate
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity investments	151,446us-gaap_MarketableSecuritiesFixedMaturities / us-gaap_FairValueByAssetClassAxis = rnr_NonUSGovernmentBackedCorporateDebtSecuritiesMember	146,467us-gaap_MarketableSecuritiesFixedMaturities / us-gaap_FairValueByAssetClassAxis = rnr_NonUSGovernmentBackedCorporateDebtSecuritiesMember
Non-U.S. government-backed corporate | Quoted Prices In Active Markets For Identical Assets (Level 1)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity investments	0us-gaap_MarketableSecuritiesFixedMaturities / us-gaap_FairValueByAssetClassAxis = rnr_NonUSGovernmentBackedCorporateDebtSecuritiesMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member	0us-gaap_MarketableSecuritiesFixedMaturities / us-gaap_FairValueByAssetClassAxis = rnr_NonUSGovernmentBackedCorporateDebtSecuritiesMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member
Non-U.S. government-backed corporate | Significant Other Observable Inputs (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity investments	151,446us-gaap_MarketableSecuritiesFixedMaturities / us-gaap_FairValueByAssetClassAxis = rnr_NonUSGovernmentBackedCorporateDebtSecuritiesMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member	146,467us-gaap_MarketableSecuritiesFixedMaturities / us-gaap_FairValueByAssetClassAxis = rnr_NonUSGovernmentBackedCorporateDebtSecuritiesMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member
Non-U.S. government-backed corporate | Significant Unobservable Inputs (Level 3)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity investments	0us-gaap_MarketableSecuritiesFixedMaturities / us-gaap_FairValueByAssetClassAxis = rnr_NonUSGovernmentBackedCorporateDebtSecuritiesMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member	0us-gaap_MarketableSecuritiesFixedMaturities / us-gaap_FairValueByAssetClassAxis = rnr_NonUSGovernmentBackedCorporateDebtSecuritiesMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member
Corporate
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity investments	1,603,024us-gaap_MarketableSecuritiesFixedMaturities / us-gaap_FairValueByAssetClassAxis = us-gaap_CorporateDebtSecuritiesMember	1,610,442us-gaap_MarketableSecuritiesFixedMaturities / us-gaap_FairValueByAssetClassAxis = us-gaap_CorporateDebtSecuritiesMember
Corporate | Quoted Prices In Active Markets For Identical Assets (Level 1)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity investments	0us-gaap_MarketableSecuritiesFixedMaturities / us-gaap_FairValueByAssetClassAxis = us-gaap_CorporateDebtSecuritiesMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member	0us-gaap_MarketableSecuritiesFixedMaturities / us-gaap_FairValueByAssetClassAxis = us-gaap_CorporateDebtSecuritiesMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member
Corporate | Significant Other Observable Inputs (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity investments	1,587,550us-gaap_MarketableSecuritiesFixedMaturities / us-gaap_FairValueByAssetClassAxis = us-gaap_CorporateDebtSecuritiesMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member	1,594,782us-gaap_MarketableSecuritiesFixedMaturities / us-gaap_FairValueByAssetClassAxis = us-gaap_CorporateDebtSecuritiesMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member
Corporate | Significant Unobservable Inputs (Level 3)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity investments	15,474us-gaap_MarketableSecuritiesFixedMaturities / us-gaap_FairValueByAssetClassAxis = us-gaap_CorporateDebtSecuritiesMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member	15,660us-gaap_MarketableSecuritiesFixedMaturities / us-gaap_FairValueByAssetClassAxis = us-gaap_CorporateDebtSecuritiesMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member
Agency mortgage-backed
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity investments	342,461us-gaap_MarketableSecuritiesFixedMaturities / us-gaap_FairValueByAssetClassAxis = us-gaap_MortgageBackedSecuritiesIssuedByUSGovernmentSponsoredEnterprisesMember	316,620us-gaap_MarketableSecuritiesFixedMaturities / us-gaap_FairValueByAssetClassAxis = us-gaap_MortgageBackedSecuritiesIssuedByUSGovernmentSponsoredEnterprisesMember
Agency mortgage-backed | Quoted Prices In Active Markets For Identical Assets (Level 1)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity investments	0us-gaap_MarketableSecuritiesFixedMaturities / us-gaap_FairValueByAssetClassAxis = us-gaap_MortgageBackedSecuritiesIssuedByUSGovernmentSponsoredEnterprisesMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member	0us-gaap_MarketableSecuritiesFixedMaturities / us-gaap_FairValueByAssetClassAxis = us-gaap_MortgageBackedSecuritiesIssuedByUSGovernmentSponsoredEnterprisesMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member
Agency mortgage-backed | Significant Other Observable Inputs (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity investments	342,461us-gaap_MarketableSecuritiesFixedMaturities / us-gaap_FairValueByAssetClassAxis = us-gaap_MortgageBackedSecuritiesIssuedByUSGovernmentSponsoredEnterprisesMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member	316,620us-gaap_MarketableSecuritiesFixedMaturities / us-gaap_FairValueByAssetClassAxis = us-gaap_MortgageBackedSecuritiesIssuedByUSGovernmentSponsoredEnterprisesMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member
Agency mortgage-backed | Significant Unobservable Inputs (Level 3)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity investments	0us-gaap_MarketableSecuritiesFixedMaturities / us-gaap_FairValueByAssetClassAxis = us-gaap_MortgageBackedSecuritiesIssuedByUSGovernmentSponsoredEnterprisesMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member	0us-gaap_MarketableSecuritiesFixedMaturities / us-gaap_FairValueByAssetClassAxis = us-gaap_MortgageBackedSecuritiesIssuedByUSGovernmentSponsoredEnterprisesMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member
Non-agency mortgage-backed
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity investments	268,102us-gaap_MarketableSecuritiesFixedMaturities / us-gaap_FairValueByAssetClassAxis = us-gaap_MortgageBackedSecuritiesIssuedByPrivateEnterprisesMember	253,050us-gaap_MarketableSecuritiesFixedMaturities / us-gaap_FairValueByAssetClassAxis = us-gaap_MortgageBackedSecuritiesIssuedByPrivateEnterprisesMember
Non-agency mortgage-backed | Quoted Prices In Active Markets For Identical Assets (Level 1)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity investments	0us-gaap_MarketableSecuritiesFixedMaturities / us-gaap_FairValueByAssetClassAxis = us-gaap_MortgageBackedSecuritiesIssuedByPrivateEnterprisesMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member	0us-gaap_MarketableSecuritiesFixedMaturities / us-gaap_FairValueByAssetClassAxis = us-gaap_MortgageBackedSecuritiesIssuedByPrivateEnterprisesMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member
Non-agency mortgage-backed | Significant Other Observable Inputs (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity investments	268,102us-gaap_MarketableSecuritiesFixedMaturities / us-gaap_FairValueByAssetClassAxis = us-gaap_MortgageBackedSecuritiesIssuedByPrivateEnterprisesMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member	253,050us-gaap_MarketableSecuritiesFixedMaturities / us-gaap_FairValueByAssetClassAxis = us-gaap_MortgageBackedSecuritiesIssuedByPrivateEnterprisesMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member
Non-agency mortgage-backed | Significant Unobservable Inputs (Level 3)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity investments	0us-gaap_MarketableSecuritiesFixedMaturities / us-gaap_FairValueByAssetClassAxis = us-gaap_MortgageBackedSecuritiesIssuedByPrivateEnterprisesMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member	0us-gaap_MarketableSecuritiesFixedMaturities / us-gaap_FairValueByAssetClassAxis = us-gaap_MortgageBackedSecuritiesIssuedByPrivateEnterprisesMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member
Commercial mortgage-backed
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity investments	361,812us-gaap_MarketableSecuritiesFixedMaturities / us-gaap_FairValueByAssetClassAxis = us-gaap_CommercialMortgageBackedSecuritiesMember	381,051us-gaap_MarketableSecuritiesFixedMaturities / us-gaap_FairValueByAssetClassAxis = us-gaap_CommercialMortgageBackedSecuritiesMember
Commercial mortgage-backed | Quoted Prices In Active Markets For Identical Assets (Level 1)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity investments	0us-gaap_MarketableSecuritiesFixedMaturities / us-gaap_FairValueByAssetClassAxis = us-gaap_CommercialMortgageBackedSecuritiesMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member	0us-gaap_MarketableSecuritiesFixedMaturities / us-gaap_FairValueByAssetClassAxis = us-gaap_CommercialMortgageBackedSecuritiesMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member
Commercial mortgage-backed | Significant Other Observable Inputs (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity investments	361,812us-gaap_MarketableSecuritiesFixedMaturities / us-gaap_FairValueByAssetClassAxis = us-gaap_CommercialMortgageBackedSecuritiesMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member	381,051us-gaap_MarketableSecuritiesFixedMaturities / us-gaap_FairValueByAssetClassAxis = us-gaap_CommercialMortgageBackedSecuritiesMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member
Commercial mortgage-backed | Significant Unobservable Inputs (Level 3)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity investments	0us-gaap_MarketableSecuritiesFixedMaturities / us-gaap_FairValueByAssetClassAxis = us-gaap_CommercialMortgageBackedSecuritiesMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member	0us-gaap_MarketableSecuritiesFixedMaturities / us-gaap_FairValueByAssetClassAxis = us-gaap_CommercialMortgageBackedSecuritiesMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member
Asset-backed
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity investments	43,234us-gaap_MarketableSecuritiesFixedMaturities / us-gaap_FairValueByAssetClassAxis = us-gaap_AssetBackedSecuritiesMember	27,610us-gaap_MarketableSecuritiesFixedMaturities / us-gaap_FairValueByAssetClassAxis = us-gaap_AssetBackedSecuritiesMember
Asset-backed | Quoted Prices In Active Markets For Identical Assets (Level 1)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity investments	0us-gaap_MarketableSecuritiesFixedMaturities / us-gaap_FairValueByAssetClassAxis = us-gaap_AssetBackedSecuritiesMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member	0us-gaap_MarketableSecuritiesFixedMaturities / us-gaap_FairValueByAssetClassAxis = us-gaap_AssetBackedSecuritiesMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member
Asset-backed | Significant Other Observable Inputs (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity investments	43,234us-gaap_MarketableSecuritiesFixedMaturities / us-gaap_FairValueByAssetClassAxis = us-gaap_AssetBackedSecuritiesMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member	27,610us-gaap_MarketableSecuritiesFixedMaturities / us-gaap_FairValueByAssetClassAxis = us-gaap_AssetBackedSecuritiesMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member
Asset-backed | Significant Unobservable Inputs (Level 3)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturity investments	0us-gaap_MarketableSecuritiesFixedMaturities / us-gaap_FairValueByAssetClassAxis = us-gaap_AssetBackedSecuritiesMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member	0us-gaap_MarketableSecuritiesFixedMaturities / us-gaap_FairValueByAssetClassAxis = us-gaap_AssetBackedSecuritiesMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member
Private equity partnerships
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other investments	271,074us-gaap_OtherInvestments / us-gaap_FairValueByAssetClassAxis = us-gaap_PrivateEquityFundsMember	281,932us-gaap_OtherInvestments / us-gaap_FairValueByAssetClassAxis = us-gaap_PrivateEquityFundsMember
Private equity partnerships | Quoted Prices In Active Markets For Identical Assets (Level 1)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other investments	0us-gaap_OtherInvestments / us-gaap_FairValueByAssetClassAxis = us-gaap_PrivateEquityFundsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member	0us-gaap_OtherInvestments / us-gaap_FairValueByAssetClassAxis = us-gaap_PrivateEquityFundsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member
Private equity partnerships | Significant Other Observable Inputs (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other investments	0us-gaap_OtherInvestments / us-gaap_FairValueByAssetClassAxis = us-gaap_PrivateEquityFundsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member	0us-gaap_OtherInvestments / us-gaap_FairValueByAssetClassAxis = us-gaap_PrivateEquityFundsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member
Private equity partnerships | Significant Unobservable Inputs (Level 3)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other investments	271,074us-gaap_OtherInvestments / us-gaap_FairValueByAssetClassAxis = us-gaap_PrivateEquityFundsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member	281,932us-gaap_OtherInvestments / us-gaap_FairValueByAssetClassAxis = us-gaap_PrivateEquityFundsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member
Catastrophe bonds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other investments	221,780us-gaap_OtherInvestments / us-gaap_FairValueByAssetClassAxis = rnr_CatastropheBondsMember	200,329us-gaap_OtherInvestments / us-gaap_FairValueByAssetClassAxis = rnr_CatastropheBondsMember
Catastrophe bonds | Quoted Prices In Active Markets For Identical Assets (Level 1)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other investments	0us-gaap_OtherInvestments / us-gaap_FairValueByAssetClassAxis = rnr_CatastropheBondsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member	0us-gaap_OtherInvestments / us-gaap_FairValueByAssetClassAxis = rnr_CatastropheBondsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member
Catastrophe bonds | Significant Other Observable Inputs (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other investments	221,780us-gaap_OtherInvestments / us-gaap_FairValueByAssetClassAxis = rnr_CatastropheBondsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member	200,329us-gaap_OtherInvestments / us-gaap_FairValueByAssetClassAxis = rnr_CatastropheBondsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member
Catastrophe bonds | Significant Unobservable Inputs (Level 3)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other investments	0us-gaap_OtherInvestments / us-gaap_FairValueByAssetClassAxis = rnr_CatastropheBondsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member	0us-gaap_OtherInvestments / us-gaap_FairValueByAssetClassAxis = rnr_CatastropheBondsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member
Senior secured bank loan funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other investments	19,679us-gaap_OtherInvestments / us-gaap_FairValueByAssetClassAxis = rnr_SeniorSecuredBankLoanFundsMember	19,316us-gaap_OtherInvestments / us-gaap_FairValueByAssetClassAxis = rnr_SeniorSecuredBankLoanFundsMember
Senior secured bank loan funds | Quoted Prices In Active Markets For Identical Assets (Level 1)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other investments	0us-gaap_OtherInvestments / us-gaap_FairValueByAssetClassAxis = rnr_SeniorSecuredBankLoanFundsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member	0us-gaap_OtherInvestments / us-gaap_FairValueByAssetClassAxis = rnr_SeniorSecuredBankLoanFundsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member
Senior secured bank loan funds | Significant Other Observable Inputs (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other investments	0us-gaap_OtherInvestments / us-gaap_FairValueByAssetClassAxis = rnr_SeniorSecuredBankLoanFundsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member	0us-gaap_OtherInvestments / us-gaap_FairValueByAssetClassAxis = rnr_SeniorSecuredBankLoanFundsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member
Senior secured bank loan funds | Significant Unobservable Inputs (Level 3)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other investments	19,679us-gaap_OtherInvestments / us-gaap_FairValueByAssetClassAxis = rnr_SeniorSecuredBankLoanFundsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member	19,316us-gaap_OtherInvestments / us-gaap_FairValueByAssetClassAxis = rnr_SeniorSecuredBankLoanFundsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member
Hedge funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other investments	2,373us-gaap_OtherInvestments / us-gaap_FairValueByAssetClassAxis = us-gaap_HedgeFundsMember	2,570us-gaap_OtherInvestments / us-gaap_FairValueByAssetClassAxis = us-gaap_HedgeFundsMember
Hedge funds | Quoted Prices In Active Markets For Identical Assets (Level 1)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other investments	0us-gaap_OtherInvestments / us-gaap_FairValueByAssetClassAxis = us-gaap_HedgeFundsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member	0us-gaap_OtherInvestments / us-gaap_FairValueByAssetClassAxis = us-gaap_HedgeFundsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member
Hedge funds | Significant Other Observable Inputs (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other investments	0us-gaap_OtherInvestments / us-gaap_FairValueByAssetClassAxis = us-gaap_HedgeFundsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member	0us-gaap_OtherInvestments / us-gaap_FairValueByAssetClassAxis = us-gaap_HedgeFundsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member
Hedge funds | Significant Unobservable Inputs (Level 3)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other investments	2,373us-gaap_OtherInvestments / us-gaap_FairValueByAssetClassAxis = us-gaap_HedgeFundsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member	2,570us-gaap_OtherInvestments / us-gaap_FairValueByAssetClassAxis = us-gaap_HedgeFundsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member
Assumed and ceded (re)insurance contracts
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other assets and (liabilities)	72,993rnr_OtherAssetsAndliabilitiesMeasuredonRecurringBasis / us-gaap_FairValueByAssetClassAxis = rnr_AssumedAndCededReInsuranceContractsMember	(8,744)rnr_OtherAssetsAndliabilitiesMeasuredonRecurringBasis / us-gaap_FairValueByAssetClassAxis = rnr_AssumedAndCededReInsuranceContractsMember
Assumed and ceded (re)insurance contracts | Quoted Prices In Active Markets For Identical Assets (Level 1)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other assets and (liabilities)	0rnr_OtherAssetsAndliabilitiesMeasuredonRecurringBasis / us-gaap_FairValueByAssetClassAxis = rnr_AssumedAndCededReInsuranceContractsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member	0rnr_OtherAssetsAndliabilitiesMeasuredonRecurringBasis / us-gaap_FairValueByAssetClassAxis = rnr_AssumedAndCededReInsuranceContractsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member
Assumed and ceded (re)insurance contracts | Significant Other Observable Inputs (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other assets and (liabilities)	0rnr_OtherAssetsAndliabilitiesMeasuredonRecurringBasis / us-gaap_FairValueByAssetClassAxis = rnr_AssumedAndCededReInsuranceContractsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member	0rnr_OtherAssetsAndliabilitiesMeasuredonRecurringBasis / us-gaap_FairValueByAssetClassAxis = rnr_AssumedAndCededReInsuranceContractsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member
Assumed and ceded (re)insurance contracts | Significant Unobservable Inputs (Level 3)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other assets and (liabilities)	72,993rnr_OtherAssetsAndliabilitiesMeasuredonRecurringBasis / us-gaap_FairValueByAssetClassAxis = rnr_AssumedAndCededReInsuranceContractsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member	(8,744)rnr_OtherAssetsAndliabilitiesMeasuredonRecurringBasis / us-gaap_FairValueByAssetClassAxis = rnr_AssumedAndCededReInsuranceContractsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member
Derivatives
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other assets and (liabilities)	7,376rnr_OtherAssetsAndliabilitiesMeasuredonRecurringBasis / us-gaap_FairValueByAssetClassAxis = rnr_DerivativesAssetsLiabilitiesMember	6,345rnr_OtherAssetsAndliabilitiesMeasuredonRecurringBasis / us-gaap_FairValueByAssetClassAxis = rnr_DerivativesAssetsLiabilitiesMember
Derivatives | Quoted Prices In Active Markets For Identical Assets (Level 1)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other assets and (liabilities)	(492)rnr_OtherAssetsAndliabilitiesMeasuredonRecurringBasis / us-gaap_FairValueByAssetClassAxis = rnr_DerivativesAssetsLiabilitiesMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member	(569)rnr_OtherAssetsAndliabilitiesMeasuredonRecurringBasis / us-gaap_FairValueByAssetClassAxis = rnr_DerivativesAssetsLiabilitiesMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member
Derivatives | Significant Other Observable Inputs (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other assets and (liabilities)	7,892rnr_OtherAssetsAndliabilitiesMeasuredonRecurringBasis / us-gaap_FairValueByAssetClassAxis = rnr_DerivativesAssetsLiabilitiesMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member	7,104rnr_OtherAssetsAndliabilitiesMeasuredonRecurringBasis / us-gaap_FairValueByAssetClassAxis = rnr_DerivativesAssetsLiabilitiesMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member
Derivatives | Significant Unobservable Inputs (Level 3)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other assets and (liabilities)	(24)rnr_OtherAssetsAndliabilitiesMeasuredonRecurringBasis / us-gaap_FairValueByAssetClassAxis = rnr_DerivativesAssetsLiabilitiesMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member	(190)rnr_OtherAssetsAndliabilitiesMeasuredonRecurringBasis / us-gaap_FairValueByAssetClassAxis = rnr_DerivativesAssetsLiabilitiesMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member
Other
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other assets and (liabilities)	(1,547)rnr_OtherAssetsAndliabilitiesMeasuredonRecurringBasis / us-gaap_FairValueByAssetClassAxis = rnr_OtherItemsMember	(11,509)rnr_OtherAssetsAndliabilitiesMeasuredonRecurringBasis / us-gaap_FairValueByAssetClassAxis = rnr_OtherItemsMember
Other | Quoted Prices In Active Markets For Identical Assets (Level 1)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other assets and (liabilities)	0rnr_OtherAssetsAndliabilitiesMeasuredonRecurringBasis / us-gaap_FairValueByAssetClassAxis = rnr_OtherItemsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member	0rnr_OtherAssetsAndliabilitiesMeasuredonRecurringBasis / us-gaap_FairValueByAssetClassAxis = rnr_OtherItemsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member
Other | Significant Other Observable Inputs (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other assets and (liabilities)	(1,547)rnr_OtherAssetsAndliabilitiesMeasuredonRecurringBasis / us-gaap_FairValueByAssetClassAxis = rnr_OtherItemsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member	(11,509)rnr_OtherAssetsAndliabilitiesMeasuredonRecurringBasis / us-gaap_FairValueByAssetClassAxis = rnr_OtherItemsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member
Other | Significant Unobservable Inputs (Level 3)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other assets and (liabilities)	$ 0rnr_OtherAssetsAndliabilitiesMeasuredonRecurringBasis / us-gaap_FairValueByAssetClassAxis = rnr_OtherItemsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member	$ 0rnr_OtherAssetsAndliabilitiesMeasuredonRecurringBasis / us-gaap_FairValueByAssetClassAxis = rnr_OtherItemsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member

X

- Definition

Other Assets And liabilities Measured on Recurring Basis

+ References

No definition available.

+ Details

Name:	rnr_OtherAssetsAndliabilitiesMeasuredonRecurringBasis
Namespace Prefix:	rnr_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

X

- Definition

This element represents the aggregate of the assets and liabilities reported on the balance sheet at period end measured at fair value by the entity. This element is intended to be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements.

+ References

No definition available.

+ Details

Name:	rnr_TotalAssetsAndLiabilitiesMeasuredAtFairValueOnRecurringBasis
Namespace Prefix:	rnr_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

X

- Details

Name:	us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

X

- Definition

For an unclassified balance sheet, this item represents investments in debt securities having predetermined or determinable maturity dates.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 1

-Subparagraph a

-Article 7



Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.7-03.1(a))

-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

+ Details

Name:	us-gaap_MarketableSecuritiesFixedMaturities
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

X

- Definition

Other investments not otherwise specified in the taxonomy.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.12)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682



Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 12

-Article 5



Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 1

-Subparagraph g

-Article 7



Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.7-03.1(f,g))

-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

+ Details

Name:	us-gaap_OtherInvestments
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

X

- Definition

Other investments not otherwise specified in the taxonomy that will be realized in a short period of time, usually less than one year or the normal operating cycle, whichever is longer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.8)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682



Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.5)

-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878



Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.7-03.1(g))

-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910



Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 5

-Article 9



Reference 5: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 1

-Subparagraph g

-Article 7

+ Details

Name:	us-gaap_OtherShortTermInvestments
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

X

- Definition

Fair value of investments in trading equity securities and other forms of trading securities that provide ownership interests.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.2)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682



Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6871852&loc=d3e26610-111562



Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 45

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6871852&loc=d3e26626-111562



Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Trading Securities

-URI http://asc.fasb.org/extlink&oid=6526789



Reference 5: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.4)

-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878



Reference 6: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.7-03.(a),1(b))

-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

+ Details

Name:	us-gaap_TradingSecuritiesEquity
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

X

- Details

Name:	us-gaap_FairValueByAssetClassAxis=rnr_AssumedAndCededReInsuranceContractsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_FairValueByAssetClassAxis=rnr_CatastropheBondsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_FairValueByAssetClassAxis=rnr_DerivativesAssetsLiabilitiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_FairValueByAssetClassAxis=rnr_NonUSGovernmentBackedCorporateDebtSecuritiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_FairValueByAssetClassAxis=rnr_OtherItemsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_FairValueByAssetClassAxis=rnr_SeniorSecuredBankLoanFundsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_FairValueByAssetClassAxis=us-gaap_AgencySecuritiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_FairValueByAssetClassAxis=us-gaap_AssetBackedSecuritiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_FairValueByAssetClassAxis=us-gaap_CommercialMortgageBackedSecuritiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_FairValueByAssetClassAxis=us-gaap_CorporateDebtSecuritiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_FairValueByAssetClassAxis=us-gaap_ForeignGovernmentDebtSecuritiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_FairValueByAssetClassAxis=us-gaap_HedgeFundsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_FairValueByAssetClassAxis=us-gaap_MortgageBackedSecuritiesIssuedByPrivateEnterprisesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_FairValueByAssetClassAxis=us-gaap_MortgageBackedSecuritiesIssuedByUSGovernmentSponsoredEnterprisesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_FairValueByAssetClassAxis=us-gaap_PrivateEquityFundsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_FairValueByAssetClassAxis=us-gaap_USStatesAndPoliticalSubdivisionsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_FairValueByAssetClassAxis=us-gaap_USTreasurySecuritiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_FairValueByFairValueHierarchyLevelAxis=us-gaap_FairValueInputsLevel1Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_FairValueByFairValueHierarchyLevelAxis=us-gaap_FairValueInputsLevel2Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_FairValueByFairValueHierarchyLevelAxis=us-gaap_FairValueInputsLevel3Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: