XML 157 R101.htm IDEA: XBRL DOCUMENT v2.4.1.9

Segment Reporting (Schedule Of Significant Components Of The Company's Revenues And Expenses) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Segment Reporting Information [Line Items]
Gross premiums written	$ 132,780us-gaap_PremiumsWrittenGross	$ 200,992us-gaap_PremiumsWrittenGross	$ 511,540us-gaap_PremiumsWrittenGross	$ 705,260us-gaap_PremiumsWrittenGross	$ 84,122us-gaap_PremiumsWrittenGross	$ 182,649us-gaap_PremiumsWrittenGross	$ 703,223us-gaap_PremiumsWrittenGross	$ 635,418us-gaap_PremiumsWrittenGross	$ 1,550,572us-gaap_PremiumsWrittenGross	$ 1,605,412us-gaap_PremiumsWrittenGross	$ 1,551,591us-gaap_PremiumsWrittenGross
Net premiums written	111,769us-gaap_PremiumsWrittenNet	159,713us-gaap_PremiumsWrittenNet	346,407us-gaap_PremiumsWrittenNet	450,347us-gaap_PremiumsWrittenNet	80,784us-gaap_PremiumsWrittenNet	127,241us-gaap_PremiumsWrittenNet	559,109us-gaap_PremiumsWrittenNet	436,813us-gaap_PremiumsWrittenNet	1,068,236us-gaap_PremiumsWrittenNet	1,203,947us-gaap_PremiumsWrittenNet	1,102,657us-gaap_PremiumsWrittenNet
Net premiums earned	256,487us-gaap_PremiumsEarnedNet	258,979us-gaap_PremiumsEarnedNet	260,416us-gaap_PremiumsEarnedNet	286,534us-gaap_PremiumsEarnedNet	256,765us-gaap_PremiumsEarnedNet	294,717us-gaap_PremiumsEarnedNet	291,889us-gaap_PremiumsEarnedNet	271,255us-gaap_PremiumsEarnedNet	1,062,416us-gaap_PremiumsEarnedNet	1,114,626us-gaap_PremiumsEarnedNet	1,069,355us-gaap_PremiumsEarnedNet
Net claims and claim expenses incurred	(12,003)us-gaap_PolicyholderBenefitsAndClaimsIncurredNet	69,647us-gaap_PolicyholderBenefitsAndClaimsIncurredNet	81,388us-gaap_PolicyholderBenefitsAndClaimsIncurredNet	58,915us-gaap_PolicyholderBenefitsAndClaimsIncurredNet	(20,854)us-gaap_PolicyholderBenefitsAndClaimsIncurredNet	60,928us-gaap_PolicyholderBenefitsAndClaimsIncurredNet	103,962us-gaap_PolicyholderBenefitsAndClaimsIncurredNet	27,251us-gaap_PolicyholderBenefitsAndClaimsIncurredNet	197,947us-gaap_PolicyholderBenefitsAndClaimsIncurredNet	171,287us-gaap_PolicyholderBenefitsAndClaimsIncurredNet	325,211us-gaap_PolicyholderBenefitsAndClaimsIncurredNet
Acquisition expenses	39,749us-gaap_DeferredPolicyAcquisitionCostAmortizationExpense	37,550us-gaap_DeferredPolicyAcquisitionCostAmortizationExpense	33,477us-gaap_DeferredPolicyAcquisitionCostAmortizationExpense	33,700us-gaap_DeferredPolicyAcquisitionCostAmortizationExpense	31,026us-gaap_DeferredPolicyAcquisitionCostAmortizationExpense	37,699us-gaap_DeferredPolicyAcquisitionCostAmortizationExpense	31,767us-gaap_DeferredPolicyAcquisitionCostAmortizationExpense	25,009us-gaap_DeferredPolicyAcquisitionCostAmortizationExpense	144,476us-gaap_DeferredPolicyAcquisitionCostAmortizationExpense	125,501us-gaap_DeferredPolicyAcquisitionCostAmortizationExpense	113,542us-gaap_DeferredPolicyAcquisitionCostAmortizationExpense
Operational expenses	55,202us-gaap_OperatingExpenses	46,972us-gaap_OperatingExpenses	45,841us-gaap_OperatingExpenses	42,624us-gaap_OperatingExpenses	57,658us-gaap_OperatingExpenses	44,672us-gaap_OperatingExpenses	42,789us-gaap_OperatingExpenses	45,986us-gaap_OperatingExpenses	190,639us-gaap_OperatingExpenses	191,105us-gaap_OperatingExpenses	179,151us-gaap_OperatingExpenses
Underwriting income (loss)									529,354rnr_UnderwritingIncomeLossNet	626,733rnr_UnderwritingIncomeLossNet	451,451rnr_UnderwritingIncomeLossNet
Net investment income	25,886us-gaap_NetInvestmentIncome	24,941us-gaap_NetInvestmentIncome	34,541us-gaap_NetInvestmentIncome	38,948us-gaap_NetInvestmentIncome	78,732us-gaap_NetInvestmentIncome	59,931us-gaap_NetInvestmentIncome	26,163us-gaap_NetInvestmentIncome	43,202us-gaap_NetInvestmentIncome	124,316us-gaap_NetInvestmentIncome	208,028us-gaap_NetInvestmentIncome	165,725us-gaap_NetInvestmentIncome
Net foreign exchange gains	(107)us-gaap_ForeignCurrencyTransactionGainLossBeforeTax	5,036us-gaap_ForeignCurrencyTransactionGainLossBeforeTax	2,392us-gaap_ForeignCurrencyTransactionGainLossBeforeTax	(1,061)us-gaap_ForeignCurrencyTransactionGainLossBeforeTax	1,747us-gaap_ForeignCurrencyTransactionGainLossBeforeTax	488us-gaap_ForeignCurrencyTransactionGainLossBeforeTax	(932)us-gaap_ForeignCurrencyTransactionGainLossBeforeTax	614us-gaap_ForeignCurrencyTransactionGainLossBeforeTax	6,260us-gaap_ForeignCurrencyTransactionGainLossBeforeTax	1,917us-gaap_ForeignCurrencyTransactionGainLossBeforeTax	5,319us-gaap_ForeignCurrencyTransactionGainLossBeforeTax
Equity in earnings of other ventures	4,838us-gaap_IncomeLossFromEquityMethodInvestments	9,806us-gaap_IncomeLossFromEquityMethodInvestments	7,232us-gaap_IncomeLossFromEquityMethodInvestments	4,199us-gaap_IncomeLossFromEquityMethodInvestments	6,274us-gaap_IncomeLossFromEquityMethodInvestments	7,313us-gaap_IncomeLossFromEquityMethodInvestments	3,772us-gaap_IncomeLossFromEquityMethodInvestments	5,835us-gaap_IncomeLossFromEquityMethodInvestments	26,075us-gaap_IncomeLossFromEquityMethodInvestments	23,194us-gaap_IncomeLossFromEquityMethodInvestments	23,238us-gaap_IncomeLossFromEquityMethodInvestments
Other loss	1,219us-gaap_OtherOperatingIncomeExpenseNet	(1,169)us-gaap_OtherOperatingIncomeExpenseNet	(535)us-gaap_OtherOperatingIncomeExpenseNet	62us-gaap_OtherOperatingIncomeExpenseNet	(173)us-gaap_OtherOperatingIncomeExpenseNet	651us-gaap_OtherOperatingIncomeExpenseNet	(1,128)us-gaap_OtherOperatingIncomeExpenseNet	(1,709)us-gaap_OtherOperatingIncomeExpenseNet	(423)us-gaap_OtherOperatingIncomeExpenseNet	(2,359)us-gaap_OtherOperatingIncomeExpenseNet	(2,120)us-gaap_OtherOperatingIncomeExpenseNet
Net realized and unrealized gains on investments	30,475us-gaap_GainLossOnInvestments	(31,097)us-gaap_GainLossOnInvestments	27,128us-gaap_GainLossOnInvestments	14,927us-gaap_GainLossOnInvestments	61,864us-gaap_GainLossOnInvestments	28,472us-gaap_GainLossOnInvestments	(69,529)us-gaap_GainLossOnInvestments	14,269us-gaap_GainLossOnInvestments	41,433us-gaap_GainLossOnInvestments	35,076us-gaap_GainLossOnInvestments	163,121us-gaap_GainLossOnInvestments
Net other-than-temporary impairments recognized in earnings									0us-gaap_OtherThanTemporaryImpairmentLossesInvestmentsPortionRecognizedInEarningsNetAvailableforsaleSecurities	0us-gaap_OtherThanTemporaryImpairmentLossesInvestmentsPortionRecognizedInEarningsNetAvailableforsaleSecurities	(343)us-gaap_OtherThanTemporaryImpairmentLossesInvestmentsPortionRecognizedInEarningsNetAvailableforsaleSecurities
Corporate expenses	(10,583)us-gaap_GeneralAndAdministrativeExpense	(3,905)us-gaap_GeneralAndAdministrativeExpense	(3,954)us-gaap_GeneralAndAdministrativeExpense	(4,545)us-gaap_GeneralAndAdministrativeExpense	(3,304)us-gaap_GeneralAndAdministrativeExpense	(4,307)us-gaap_GeneralAndAdministrativeExpense	(21,529)us-gaap_GeneralAndAdministrativeExpense	(4,482)us-gaap_GeneralAndAdministrativeExpense	(22,987)us-gaap_GeneralAndAdministrativeExpense	(33,622)us-gaap_GeneralAndAdministrativeExpense	(16,456)us-gaap_GeneralAndAdministrativeExpense
Interest expense	(4,289)us-gaap_InterestExpense	(4,290)us-gaap_InterestExpense	(4,292)us-gaap_InterestExpense	(4,293)us-gaap_InterestExpense	(4,297)us-gaap_InterestExpense	(4,298)us-gaap_InterestExpense	(4,300)us-gaap_InterestExpense	(5,034)us-gaap_InterestExpense	(17,164)us-gaap_InterestExpense	(17,929)us-gaap_InterestExpense	(23,097)us-gaap_InterestExpense
Income from continuing operations before taxes	220,978us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	104,132us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	162,222us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	199,532us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	329,778us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	239,668us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	45,888us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	225,704us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	686,864us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	841,038us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	766,838us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest
Income tax (expense) benefit	(401)us-gaap_IncomeTaxExpenseBenefit	(245)us-gaap_IncomeTaxExpenseBenefit	204us-gaap_IncomeTaxExpenseBenefit	(166)us-gaap_IncomeTaxExpenseBenefit	(1,336)us-gaap_IncomeTaxExpenseBenefit	(223)us-gaap_IncomeTaxExpenseBenefit	(11)us-gaap_IncomeTaxExpenseBenefit	(122)us-gaap_IncomeTaxExpenseBenefit	(608)us-gaap_IncomeTaxExpenseBenefit	(1,692)us-gaap_IncomeTaxExpenseBenefit	(1,413)us-gaap_IncomeTaxExpenseBenefit
Income (loss) from discontinued operations	0us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTax	0us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTax	0us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTax	0us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTax	0us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTax	(9,779)us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTax	2,427us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTax	9,774us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTax	0us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTax	2,422us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTax	(16,476)us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTax
Net income attributable to noncontrolling interests	(44,215)us-gaap_NetIncomeLossAttributableToNoncontrollingInterest	(30,477)us-gaap_NetIncomeLossAttributableToNoncontrollingInterest	(36,078)us-gaap_NetIncomeLossAttributableToNoncontrollingInterest	(42,768)us-gaap_NetIncomeLossAttributableToNoncontrollingInterest	(54,191)us-gaap_NetIncomeLossAttributableToNoncontrollingInterest	(44,331)us-gaap_NetIncomeLossAttributableToNoncontrollingInterest	(14,015)us-gaap_NetIncomeLossAttributableToNoncontrollingInterest	(38,607)us-gaap_NetIncomeLossAttributableToNoncontrollingInterest	(153,538)us-gaap_NetIncomeLossAttributableToNoncontrollingInterest	(151,144)us-gaap_NetIncomeLossAttributableToNoncontrollingInterest	(148,040)us-gaap_NetIncomeLossAttributableToNoncontrollingInterest
Dividends on preference shares	(5,595)us-gaap_DividendsPreferredStock	(5,595)us-gaap_DividendsPreferredStock	(5,596)us-gaap_DividendsPreferredStock	(5,595)us-gaap_DividendsPreferredStock	(5,595)us-gaap_DividendsPreferredStock	(5,595)us-gaap_DividendsPreferredStock	(7,483)us-gaap_DividendsPreferredStock	(6,275)us-gaap_DividendsPreferredStock	(22,381)us-gaap_DividendsPreferredStock	(24,948)us-gaap_DividendsPreferredStock	(34,895)us-gaap_DividendsPreferredStock
Net income available to RenaissanceRe common shareholders	170,767us-gaap_NetIncomeLossAvailableToCommonStockholdersBasic	67,815us-gaap_NetIncomeLossAvailableToCommonStockholdersBasic	120,752us-gaap_NetIncomeLossAvailableToCommonStockholdersBasic	151,003us-gaap_NetIncomeLossAvailableToCommonStockholdersBasic	268,656us-gaap_NetIncomeLossAvailableToCommonStockholdersBasic	179,740us-gaap_NetIncomeLossAvailableToCommonStockholdersBasic	26,806us-gaap_NetIncomeLossAvailableToCommonStockholdersBasic	190,474us-gaap_NetIncomeLossAvailableToCommonStockholdersBasic	510,337us-gaap_NetIncomeLossAvailableToCommonStockholdersBasic	665,676us-gaap_NetIncomeLossAvailableToCommonStockholdersBasic	566,014us-gaap_NetIncomeLossAvailableToCommonStockholdersBasic
Net claims and claim expenses incurred - current accident year									341,745us-gaap_SupplementalInformationForPropertyCasualtyInsuranceUnderwritersCurrentYearClaimsAndClaimsAdjustmentExpense	315,241us-gaap_SupplementalInformationForPropertyCasualtyInsuranceUnderwritersCurrentYearClaimsAndClaimsAdjustmentExpense	483,180us-gaap_SupplementalInformationForPropertyCasualtyInsuranceUnderwritersCurrentYearClaimsAndClaimsAdjustmentExpense
Net claims and claim expenses incurred – prior accident years									(143,798)us-gaap_SupplementalInformationForPropertyCasualtyInsuranceUnderwritersPriorYearClaimsAndClaimsAdjustmentExpense	(143,954)us-gaap_SupplementalInformationForPropertyCasualtyInsuranceUnderwritersPriorYearClaimsAndClaimsAdjustmentExpense	(157,969)us-gaap_SupplementalInformationForPropertyCasualtyInsuranceUnderwritersPriorYearClaimsAndClaimsAdjustmentExpense
Total net incurred									197,947us-gaap_LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseIncurredClaims1	171,287us-gaap_LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseIncurredClaims1	325,211us-gaap_LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseIncurredClaims1
Net claims and claim expense ratio - current accident year									32.20%rnr_NetClaimsAndClaimsExpenseRatioCurrentYear	28.30%rnr_NetClaimsAndClaimsExpenseRatioCurrentYear	45.20%rnr_NetClaimsAndClaimsExpenseRatioCurrentYear
Net claims and claim expense ratio - prior accident years									(13.60%)rnr_NetClaimsAndClaimExpenseRatioPriorYears	(12.90%)rnr_NetClaimsAndClaimExpenseRatioPriorYears	(14.80%)rnr_NetClaimsAndClaimExpenseRatioPriorYears
Net claims and claim expense ratio - calendar year									18.60%us-gaap_LossRatio	15.40%us-gaap_LossRatio	30.40%us-gaap_LossRatio
Underwriting expense ratio									31.60%us-gaap_UnderwritingExpenseRatio	28.40%us-gaap_UnderwritingExpenseRatio	27.40%us-gaap_UnderwritingExpenseRatio
Combined ratio									50.20%us-gaap_CombinedRatio	43.80%us-gaap_CombinedRatio	57.80%us-gaap_CombinedRatio
Catastrophe Reinsurance
Segment Reporting Information [Line Items]
Gross premiums written									933,969us-gaap_PremiumsWrittenGross / us-gaap_StatementBusinessSegmentsAxis = rnr_CatastropheReinsuranceSegmentMember	1,120,379us-gaap_PremiumsWrittenGross / us-gaap_StatementBusinessSegmentsAxis = rnr_CatastropheReinsuranceSegmentMember	1,182,207us-gaap_PremiumsWrittenGross / us-gaap_StatementBusinessSegmentsAxis = rnr_CatastropheReinsuranceSegmentMember
Net premiums written									541,608us-gaap_PremiumsWrittenNet / us-gaap_StatementBusinessSegmentsAxis = rnr_CatastropheReinsuranceSegmentMember	753,078us-gaap_PremiumsWrittenNet / us-gaap_StatementBusinessSegmentsAxis = rnr_CatastropheReinsuranceSegmentMember	766,035us-gaap_PremiumsWrittenNet / us-gaap_StatementBusinessSegmentsAxis = rnr_CatastropheReinsuranceSegmentMember
Net premiums earned									590,845us-gaap_PremiumsEarnedNet / us-gaap_StatementBusinessSegmentsAxis = rnr_CatastropheReinsuranceSegmentMember	723,705us-gaap_PremiumsEarnedNet / us-gaap_StatementBusinessSegmentsAxis = rnr_CatastropheReinsuranceSegmentMember	781,738us-gaap_PremiumsEarnedNet / us-gaap_StatementBusinessSegmentsAxis = rnr_CatastropheReinsuranceSegmentMember
Net claims and claim expenses incurred									1,757us-gaap_PolicyholderBenefitsAndClaimsIncurredNet / us-gaap_StatementBusinessSegmentsAxis = rnr_CatastropheReinsuranceSegmentMember	7,908us-gaap_PolicyholderBenefitsAndClaimsIncurredNet / us-gaap_StatementBusinessSegmentsAxis = rnr_CatastropheReinsuranceSegmentMember	165,209us-gaap_PolicyholderBenefitsAndClaimsIncurredNet / us-gaap_StatementBusinessSegmentsAxis = rnr_CatastropheReinsuranceSegmentMember
Acquisition expenses									43,161us-gaap_DeferredPolicyAcquisitionCostAmortizationExpense / us-gaap_StatementBusinessSegmentsAxis = rnr_CatastropheReinsuranceSegmentMember	49,161us-gaap_DeferredPolicyAcquisitionCostAmortizationExpense / us-gaap_StatementBusinessSegmentsAxis = rnr_CatastropheReinsuranceSegmentMember	66,665us-gaap_DeferredPolicyAcquisitionCostAmortizationExpense / us-gaap_StatementBusinessSegmentsAxis = rnr_CatastropheReinsuranceSegmentMember
Operational expenses									95,851us-gaap_OperatingExpenses / us-gaap_StatementBusinessSegmentsAxis = rnr_CatastropheReinsuranceSegmentMember	108,130us-gaap_OperatingExpenses / us-gaap_StatementBusinessSegmentsAxis = rnr_CatastropheReinsuranceSegmentMember	103,811us-gaap_OperatingExpenses / us-gaap_StatementBusinessSegmentsAxis = rnr_CatastropheReinsuranceSegmentMember
Underwriting income (loss)									450,076rnr_UnderwritingIncomeLossNet / us-gaap_StatementBusinessSegmentsAxis = rnr_CatastropheReinsuranceSegmentMember	558,506rnr_UnderwritingIncomeLossNet / us-gaap_StatementBusinessSegmentsAxis = rnr_CatastropheReinsuranceSegmentMember	446,053rnr_UnderwritingIncomeLossNet / us-gaap_StatementBusinessSegmentsAxis = rnr_CatastropheReinsuranceSegmentMember
Net claims and claim expenses incurred - current accident year									67,268us-gaap_SupplementalInformationForPropertyCasualtyInsuranceUnderwritersCurrentYearClaimsAndClaimsAdjustmentExpense / us-gaap_StatementBusinessSegmentsAxis = rnr_CatastropheReinsuranceSegmentMember	109,945us-gaap_SupplementalInformationForPropertyCasualtyInsuranceUnderwritersCurrentYearClaimsAndClaimsAdjustmentExpense / us-gaap_StatementBusinessSegmentsAxis = rnr_CatastropheReinsuranceSegmentMember	275,777us-gaap_SupplementalInformationForPropertyCasualtyInsuranceUnderwritersCurrentYearClaimsAndClaimsAdjustmentExpense / us-gaap_StatementBusinessSegmentsAxis = rnr_CatastropheReinsuranceSegmentMember
Net claims and claim expenses incurred – prior accident years									(65,511)us-gaap_SupplementalInformationForPropertyCasualtyInsuranceUnderwritersPriorYearClaimsAndClaimsAdjustmentExpense / us-gaap_StatementBusinessSegmentsAxis = rnr_CatastropheReinsuranceSegmentMember	(102,037)us-gaap_SupplementalInformationForPropertyCasualtyInsuranceUnderwritersPriorYearClaimsAndClaimsAdjustmentExpense / us-gaap_StatementBusinessSegmentsAxis = rnr_CatastropheReinsuranceSegmentMember	(110,568)us-gaap_SupplementalInformationForPropertyCasualtyInsuranceUnderwritersPriorYearClaimsAndClaimsAdjustmentExpense / us-gaap_StatementBusinessSegmentsAxis = rnr_CatastropheReinsuranceSegmentMember
Total net incurred									1,757us-gaap_LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseIncurredClaims1 / us-gaap_StatementBusinessSegmentsAxis = rnr_CatastropheReinsuranceSegmentMember	7,908us-gaap_LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseIncurredClaims1 / us-gaap_StatementBusinessSegmentsAxis = rnr_CatastropheReinsuranceSegmentMember	165,209us-gaap_LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseIncurredClaims1 / us-gaap_StatementBusinessSegmentsAxis = rnr_CatastropheReinsuranceSegmentMember
Net claims and claim expense ratio - current accident year									11.40%rnr_NetClaimsAndClaimsExpenseRatioCurrentYear / us-gaap_StatementBusinessSegmentsAxis = rnr_CatastropheReinsuranceSegmentMember	15.20%rnr_NetClaimsAndClaimsExpenseRatioCurrentYear / us-gaap_StatementBusinessSegmentsAxis = rnr_CatastropheReinsuranceSegmentMember	35.30%rnr_NetClaimsAndClaimsExpenseRatioCurrentYear / us-gaap_StatementBusinessSegmentsAxis = rnr_CatastropheReinsuranceSegmentMember
Net claims and claim expense ratio - prior accident years									(11.10%)rnr_NetClaimsAndClaimExpenseRatioPriorYears / us-gaap_StatementBusinessSegmentsAxis = rnr_CatastropheReinsuranceSegmentMember	(14.10%)rnr_NetClaimsAndClaimExpenseRatioPriorYears / us-gaap_StatementBusinessSegmentsAxis = rnr_CatastropheReinsuranceSegmentMember	(14.20%)rnr_NetClaimsAndClaimExpenseRatioPriorYears / us-gaap_StatementBusinessSegmentsAxis = rnr_CatastropheReinsuranceSegmentMember
Net claims and claim expense ratio - calendar year									0.30%us-gaap_LossRatio / us-gaap_StatementBusinessSegmentsAxis = rnr_CatastropheReinsuranceSegmentMember	1.10%us-gaap_LossRatio / us-gaap_StatementBusinessSegmentsAxis = rnr_CatastropheReinsuranceSegmentMember	21.10%us-gaap_LossRatio / us-gaap_StatementBusinessSegmentsAxis = rnr_CatastropheReinsuranceSegmentMember
Underwriting expense ratio									23.50%us-gaap_UnderwritingExpenseRatio / us-gaap_StatementBusinessSegmentsAxis = rnr_CatastropheReinsuranceSegmentMember	21.70%us-gaap_UnderwritingExpenseRatio / us-gaap_StatementBusinessSegmentsAxis = rnr_CatastropheReinsuranceSegmentMember	21.80%us-gaap_UnderwritingExpenseRatio / us-gaap_StatementBusinessSegmentsAxis = rnr_CatastropheReinsuranceSegmentMember
Combined ratio									23.80%us-gaap_CombinedRatio / us-gaap_StatementBusinessSegmentsAxis = rnr_CatastropheReinsuranceSegmentMember	22.80%us-gaap_CombinedRatio / us-gaap_StatementBusinessSegmentsAxis = rnr_CatastropheReinsuranceSegmentMember	42.90%us-gaap_CombinedRatio / us-gaap_StatementBusinessSegmentsAxis = rnr_CatastropheReinsuranceSegmentMember
Specialty Reinsurance
Segment Reporting Information [Line Items]
Gross premiums written									346,638us-gaap_PremiumsWrittenGross / us-gaap_StatementBusinessSegmentsAxis = rnr_SpecialtyReinsuranceSegmentMember	259,489us-gaap_PremiumsWrittenGross / us-gaap_StatementBusinessSegmentsAxis = rnr_SpecialtyReinsuranceSegmentMember	209,887us-gaap_PremiumsWrittenGross / us-gaap_StatementBusinessSegmentsAxis = rnr_SpecialtyReinsuranceSegmentMember
Net premiums written									295,855us-gaap_PremiumsWrittenNet / us-gaap_StatementBusinessSegmentsAxis = rnr_SpecialtyReinsuranceSegmentMember	248,562us-gaap_PremiumsWrittenNet / us-gaap_StatementBusinessSegmentsAxis = rnr_SpecialtyReinsuranceSegmentMember	201,552us-gaap_PremiumsWrittenNet / us-gaap_StatementBusinessSegmentsAxis = rnr_SpecialtyReinsuranceSegmentMember
Net premiums earned									253,537us-gaap_PremiumsEarnedNet / us-gaap_StatementBusinessSegmentsAxis = rnr_SpecialtyReinsuranceSegmentMember	214,306us-gaap_PremiumsEarnedNet / us-gaap_StatementBusinessSegmentsAxis = rnr_SpecialtyReinsuranceSegmentMember	164,685us-gaap_PremiumsEarnedNet / us-gaap_StatementBusinessSegmentsAxis = rnr_SpecialtyReinsuranceSegmentMember
Net claims and claim expenses incurred									88,502us-gaap_PolicyholderBenefitsAndClaimsIncurredNet / us-gaap_StatementBusinessSegmentsAxis = rnr_SpecialtyReinsuranceSegmentMember	67,236us-gaap_PolicyholderBenefitsAndClaimsIncurredNet / us-gaap_StatementBusinessSegmentsAxis = rnr_SpecialtyReinsuranceSegmentMember	76,813us-gaap_PolicyholderBenefitsAndClaimsIncurredNet / us-gaap_StatementBusinessSegmentsAxis = rnr_SpecialtyReinsuranceSegmentMember
Acquisition expenses									60,936us-gaap_DeferredPolicyAcquisitionCostAmortizationExpense / us-gaap_StatementBusinessSegmentsAxis = rnr_SpecialtyReinsuranceSegmentMember	41,538us-gaap_DeferredPolicyAcquisitionCostAmortizationExpense / us-gaap_StatementBusinessSegmentsAxis = rnr_SpecialtyReinsuranceSegmentMember	23,826us-gaap_DeferredPolicyAcquisitionCostAmortizationExpense / us-gaap_StatementBusinessSegmentsAxis = rnr_SpecialtyReinsuranceSegmentMember
Operational expenses									43,370us-gaap_OperatingExpenses / us-gaap_StatementBusinessSegmentsAxis = rnr_SpecialtyReinsuranceSegmentMember	31,780us-gaap_OperatingExpenses / us-gaap_StatementBusinessSegmentsAxis = rnr_SpecialtyReinsuranceSegmentMember	29,124us-gaap_OperatingExpenses / us-gaap_StatementBusinessSegmentsAxis = rnr_SpecialtyReinsuranceSegmentMember
Underwriting income (loss)									60,729rnr_UnderwritingIncomeLossNet / us-gaap_StatementBusinessSegmentsAxis = rnr_SpecialtyReinsuranceSegmentMember	73,752rnr_UnderwritingIncomeLossNet / us-gaap_StatementBusinessSegmentsAxis = rnr_SpecialtyReinsuranceSegmentMember	34,922rnr_UnderwritingIncomeLossNet / us-gaap_StatementBusinessSegmentsAxis = rnr_SpecialtyReinsuranceSegmentMember
Net claims and claim expenses incurred - current accident year									144,411us-gaap_SupplementalInformationForPropertyCasualtyInsuranceUnderwritersCurrentYearClaimsAndClaimsAdjustmentExpense / us-gaap_StatementBusinessSegmentsAxis = rnr_SpecialtyReinsuranceSegmentMember	101,347us-gaap_SupplementalInformationForPropertyCasualtyInsuranceUnderwritersCurrentYearClaimsAndClaimsAdjustmentExpense / us-gaap_StatementBusinessSegmentsAxis = rnr_SpecialtyReinsuranceSegmentMember	110,959us-gaap_SupplementalInformationForPropertyCasualtyInsuranceUnderwritersCurrentYearClaimsAndClaimsAdjustmentExpense / us-gaap_StatementBusinessSegmentsAxis = rnr_SpecialtyReinsuranceSegmentMember
Net claims and claim expenses incurred – prior accident years									(55,909)us-gaap_SupplementalInformationForPropertyCasualtyInsuranceUnderwritersPriorYearClaimsAndClaimsAdjustmentExpense / us-gaap_StatementBusinessSegmentsAxis = rnr_SpecialtyReinsuranceSegmentMember	(34,111)us-gaap_SupplementalInformationForPropertyCasualtyInsuranceUnderwritersPriorYearClaimsAndClaimsAdjustmentExpense / us-gaap_StatementBusinessSegmentsAxis = rnr_SpecialtyReinsuranceSegmentMember	(34,146)us-gaap_SupplementalInformationForPropertyCasualtyInsuranceUnderwritersPriorYearClaimsAndClaimsAdjustmentExpense / us-gaap_StatementBusinessSegmentsAxis = rnr_SpecialtyReinsuranceSegmentMember
Total net incurred									88,502us-gaap_LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseIncurredClaims1 / us-gaap_StatementBusinessSegmentsAxis = rnr_SpecialtyReinsuranceSegmentMember	67,236us-gaap_LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseIncurredClaims1 / us-gaap_StatementBusinessSegmentsAxis = rnr_SpecialtyReinsuranceSegmentMember	76,813us-gaap_LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseIncurredClaims1 / us-gaap_StatementBusinessSegmentsAxis = rnr_SpecialtyReinsuranceSegmentMember
Net claims and claim expense ratio - current accident year									57.00%rnr_NetClaimsAndClaimsExpenseRatioCurrentYear / us-gaap_StatementBusinessSegmentsAxis = rnr_SpecialtyReinsuranceSegmentMember	47.30%rnr_NetClaimsAndClaimsExpenseRatioCurrentYear / us-gaap_StatementBusinessSegmentsAxis = rnr_SpecialtyReinsuranceSegmentMember	67.40%rnr_NetClaimsAndClaimsExpenseRatioCurrentYear / us-gaap_StatementBusinessSegmentsAxis = rnr_SpecialtyReinsuranceSegmentMember
Net claims and claim expense ratio - prior accident years									(22.10%)rnr_NetClaimsAndClaimExpenseRatioPriorYears / us-gaap_StatementBusinessSegmentsAxis = rnr_SpecialtyReinsuranceSegmentMember	(15.90%)rnr_NetClaimsAndClaimExpenseRatioPriorYears / us-gaap_StatementBusinessSegmentsAxis = rnr_SpecialtyReinsuranceSegmentMember	(20.80%)rnr_NetClaimsAndClaimExpenseRatioPriorYears / us-gaap_StatementBusinessSegmentsAxis = rnr_SpecialtyReinsuranceSegmentMember
Net claims and claim expense ratio - calendar year									34.90%us-gaap_LossRatio / us-gaap_StatementBusinessSegmentsAxis = rnr_SpecialtyReinsuranceSegmentMember	31.40%us-gaap_LossRatio / us-gaap_StatementBusinessSegmentsAxis = rnr_SpecialtyReinsuranceSegmentMember	46.60%us-gaap_LossRatio / us-gaap_StatementBusinessSegmentsAxis = rnr_SpecialtyReinsuranceSegmentMember
Underwriting expense ratio									41.10%us-gaap_UnderwritingExpenseRatio / us-gaap_StatementBusinessSegmentsAxis = rnr_SpecialtyReinsuranceSegmentMember	34.20%us-gaap_UnderwritingExpenseRatio / us-gaap_StatementBusinessSegmentsAxis = rnr_SpecialtyReinsuranceSegmentMember	32.20%us-gaap_UnderwritingExpenseRatio / us-gaap_StatementBusinessSegmentsAxis = rnr_SpecialtyReinsuranceSegmentMember
Combined ratio									76.00%us-gaap_CombinedRatio / us-gaap_StatementBusinessSegmentsAxis = rnr_SpecialtyReinsuranceSegmentMember	65.60%us-gaap_CombinedRatio / us-gaap_StatementBusinessSegmentsAxis = rnr_SpecialtyReinsuranceSegmentMember	78.80%us-gaap_CombinedRatio / us-gaap_StatementBusinessSegmentsAxis = rnr_SpecialtyReinsuranceSegmentMember
Lloyd's
Segment Reporting Information [Line Items]
Gross premiums written									269,656us-gaap_PremiumsWrittenGross / us-gaap_StatementBusinessSegmentsAxis = rnr_LloydsSegmentMember	226,532us-gaap_PremiumsWrittenGross / us-gaap_StatementBusinessSegmentsAxis = rnr_LloydsSegmentMember	159,987us-gaap_PremiumsWrittenGross / us-gaap_StatementBusinessSegmentsAxis = rnr_LloydsSegmentMember
Net premiums written									230,429us-gaap_PremiumsWrittenNet / us-gaap_StatementBusinessSegmentsAxis = rnr_LloydsSegmentMember	201,697us-gaap_PremiumsWrittenNet / us-gaap_StatementBusinessSegmentsAxis = rnr_LloydsSegmentMember	135,131us-gaap_PremiumsWrittenNet / us-gaap_StatementBusinessSegmentsAxis = rnr_LloydsSegmentMember
Net premiums earned									217,666us-gaap_PremiumsEarnedNet / us-gaap_StatementBusinessSegmentsAxis = rnr_LloydsSegmentMember	176,029us-gaap_PremiumsEarnedNet / us-gaap_StatementBusinessSegmentsAxis = rnr_LloydsSegmentMember	122,968us-gaap_PremiumsEarnedNet / us-gaap_StatementBusinessSegmentsAxis = rnr_LloydsSegmentMember
Net claims and claim expenses incurred									113,825us-gaap_PolicyholderBenefitsAndClaimsIncurredNet / us-gaap_StatementBusinessSegmentsAxis = rnr_LloydsSegmentMember	95,693us-gaap_PolicyholderBenefitsAndClaimsIncurredNet / us-gaap_StatementBusinessSegmentsAxis = rnr_LloydsSegmentMember	80,242us-gaap_PolicyholderBenefitsAndClaimsIncurredNet / us-gaap_StatementBusinessSegmentsAxis = rnr_LloydsSegmentMember
Acquisition expenses									46,927us-gaap_DeferredPolicyAcquisitionCostAmortizationExpense / us-gaap_StatementBusinessSegmentsAxis = rnr_LloydsSegmentMember	34,823us-gaap_DeferredPolicyAcquisitionCostAmortizationExpense / us-gaap_StatementBusinessSegmentsAxis = rnr_LloydsSegmentMember	22,864us-gaap_DeferredPolicyAcquisitionCostAmortizationExpense / us-gaap_StatementBusinessSegmentsAxis = rnr_LloydsSegmentMember
Operational expenses									51,115us-gaap_OperatingExpenses / us-gaap_StatementBusinessSegmentsAxis = rnr_LloydsSegmentMember	50,540us-gaap_OperatingExpenses / us-gaap_StatementBusinessSegmentsAxis = rnr_LloydsSegmentMember	45,680us-gaap_OperatingExpenses / us-gaap_StatementBusinessSegmentsAxis = rnr_LloydsSegmentMember
Underwriting income (loss)									5,799rnr_UnderwritingIncomeLossNet / us-gaap_StatementBusinessSegmentsAxis = rnr_LloydsSegmentMember	(5,027)rnr_UnderwritingIncomeLossNet / us-gaap_StatementBusinessSegmentsAxis = rnr_LloydsSegmentMember	(25,818)rnr_UnderwritingIncomeLossNet / us-gaap_StatementBusinessSegmentsAxis = rnr_LloydsSegmentMember
Net claims and claim expenses incurred - current accident year									130,066us-gaap_SupplementalInformationForPropertyCasualtyInsuranceUnderwritersCurrentYearClaimsAndClaimsAdjustmentExpense / us-gaap_StatementBusinessSegmentsAxis = rnr_LloydsSegmentMember	103,949us-gaap_SupplementalInformationForPropertyCasualtyInsuranceUnderwritersCurrentYearClaimsAndClaimsAdjustmentExpense / us-gaap_StatementBusinessSegmentsAxis = rnr_LloydsSegmentMember	96,444us-gaap_SupplementalInformationForPropertyCasualtyInsuranceUnderwritersCurrentYearClaimsAndClaimsAdjustmentExpense / us-gaap_StatementBusinessSegmentsAxis = rnr_LloydsSegmentMember
Net claims and claim expenses incurred – prior accident years									(16,241)us-gaap_SupplementalInformationForPropertyCasualtyInsuranceUnderwritersPriorYearClaimsAndClaimsAdjustmentExpense / us-gaap_StatementBusinessSegmentsAxis = rnr_LloydsSegmentMember	(8,256)us-gaap_SupplementalInformationForPropertyCasualtyInsuranceUnderwritersPriorYearClaimsAndClaimsAdjustmentExpense / us-gaap_StatementBusinessSegmentsAxis = rnr_LloydsSegmentMember	(16,202)us-gaap_SupplementalInformationForPropertyCasualtyInsuranceUnderwritersPriorYearClaimsAndClaimsAdjustmentExpense / us-gaap_StatementBusinessSegmentsAxis = rnr_LloydsSegmentMember
Total net incurred									113,825us-gaap_LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseIncurredClaims1 / us-gaap_StatementBusinessSegmentsAxis = rnr_LloydsSegmentMember	95,693us-gaap_LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseIncurredClaims1 / us-gaap_StatementBusinessSegmentsAxis = rnr_LloydsSegmentMember	80,242us-gaap_LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseIncurredClaims1 / us-gaap_StatementBusinessSegmentsAxis = rnr_LloydsSegmentMember
Net claims and claim expense ratio - current accident year									59.80%rnr_NetClaimsAndClaimsExpenseRatioCurrentYear / us-gaap_StatementBusinessSegmentsAxis = rnr_LloydsSegmentMember	59.10%rnr_NetClaimsAndClaimsExpenseRatioCurrentYear / us-gaap_StatementBusinessSegmentsAxis = rnr_LloydsSegmentMember	78.40%rnr_NetClaimsAndClaimsExpenseRatioCurrentYear / us-gaap_StatementBusinessSegmentsAxis = rnr_LloydsSegmentMember
Net claims and claim expense ratio - prior accident years									(7.50%)rnr_NetClaimsAndClaimExpenseRatioPriorYears / us-gaap_StatementBusinessSegmentsAxis = rnr_LloydsSegmentMember	(4.70%)rnr_NetClaimsAndClaimExpenseRatioPriorYears / us-gaap_StatementBusinessSegmentsAxis = rnr_LloydsSegmentMember	(13.10%)rnr_NetClaimsAndClaimExpenseRatioPriorYears / us-gaap_StatementBusinessSegmentsAxis = rnr_LloydsSegmentMember
Net claims and claim expense ratio - calendar year									52.30%us-gaap_LossRatio / us-gaap_StatementBusinessSegmentsAxis = rnr_LloydsSegmentMember	54.40%us-gaap_LossRatio / us-gaap_StatementBusinessSegmentsAxis = rnr_LloydsSegmentMember	65.30%us-gaap_LossRatio / us-gaap_StatementBusinessSegmentsAxis = rnr_LloydsSegmentMember
Underwriting expense ratio									45.00%us-gaap_UnderwritingExpenseRatio / us-gaap_StatementBusinessSegmentsAxis = rnr_LloydsSegmentMember	48.50%us-gaap_UnderwritingExpenseRatio / us-gaap_StatementBusinessSegmentsAxis = rnr_LloydsSegmentMember	55.70%us-gaap_UnderwritingExpenseRatio / us-gaap_StatementBusinessSegmentsAxis = rnr_LloydsSegmentMember
Combined ratio									97.30%us-gaap_CombinedRatio / us-gaap_StatementBusinessSegmentsAxis = rnr_LloydsSegmentMember	102.90%us-gaap_CombinedRatio / us-gaap_StatementBusinessSegmentsAxis = rnr_LloydsSegmentMember	121.00%us-gaap_CombinedRatio / us-gaap_StatementBusinessSegmentsAxis = rnr_LloydsSegmentMember
Other
Segment Reporting Information [Line Items]
Gross premiums written									309us-gaap_PremiumsWrittenGross / us-gaap_StatementBusinessSegmentsAxis = us-gaap_AllOtherSegmentsMember	(988)us-gaap_PremiumsWrittenGross / us-gaap_StatementBusinessSegmentsAxis = us-gaap_AllOtherSegmentsMember	(490)us-gaap_PremiumsWrittenGross / us-gaap_StatementBusinessSegmentsAxis = us-gaap_AllOtherSegmentsMember
Net premiums written									344us-gaap_PremiumsWrittenNet / us-gaap_StatementBusinessSegmentsAxis = us-gaap_AllOtherSegmentsMember	610us-gaap_PremiumsWrittenNet / us-gaap_StatementBusinessSegmentsAxis = us-gaap_AllOtherSegmentsMember	(61)us-gaap_PremiumsWrittenNet / us-gaap_StatementBusinessSegmentsAxis = us-gaap_AllOtherSegmentsMember
Net premiums earned									368us-gaap_PremiumsEarnedNet / us-gaap_StatementBusinessSegmentsAxis = us-gaap_AllOtherSegmentsMember	586us-gaap_PremiumsEarnedNet / us-gaap_StatementBusinessSegmentsAxis = us-gaap_AllOtherSegmentsMember	(36)us-gaap_PremiumsEarnedNet / us-gaap_StatementBusinessSegmentsAxis = us-gaap_AllOtherSegmentsMember
Net claims and claim expenses incurred									(6,137)us-gaap_PolicyholderBenefitsAndClaimsIncurredNet / us-gaap_StatementBusinessSegmentsAxis = us-gaap_AllOtherSegmentsMember	450us-gaap_PolicyholderBenefitsAndClaimsIncurredNet / us-gaap_StatementBusinessSegmentsAxis = us-gaap_AllOtherSegmentsMember	2,947us-gaap_PolicyholderBenefitsAndClaimsIncurredNet / us-gaap_StatementBusinessSegmentsAxis = us-gaap_AllOtherSegmentsMember
Acquisition expenses									(6,548)us-gaap_DeferredPolicyAcquisitionCostAmortizationExpense / us-gaap_StatementBusinessSegmentsAxis = us-gaap_AllOtherSegmentsMember	(21)us-gaap_DeferredPolicyAcquisitionCostAmortizationExpense / us-gaap_StatementBusinessSegmentsAxis = us-gaap_AllOtherSegmentsMember	187us-gaap_DeferredPolicyAcquisitionCostAmortizationExpense / us-gaap_StatementBusinessSegmentsAxis = us-gaap_AllOtherSegmentsMember
Operational expenses									303us-gaap_OperatingExpenses / us-gaap_StatementBusinessSegmentsAxis = us-gaap_AllOtherSegmentsMember	655us-gaap_OperatingExpenses / us-gaap_StatementBusinessSegmentsAxis = us-gaap_AllOtherSegmentsMember	536us-gaap_OperatingExpenses / us-gaap_StatementBusinessSegmentsAxis = us-gaap_AllOtherSegmentsMember
Underwriting income (loss)									12,750rnr_UnderwritingIncomeLossNet / us-gaap_StatementBusinessSegmentsAxis = us-gaap_AllOtherSegmentsMember	(498)rnr_UnderwritingIncomeLossNet / us-gaap_StatementBusinessSegmentsAxis = us-gaap_AllOtherSegmentsMember	(3,706)rnr_UnderwritingIncomeLossNet / us-gaap_StatementBusinessSegmentsAxis = us-gaap_AllOtherSegmentsMember
Net investment income									124,316us-gaap_NetInvestmentIncome / us-gaap_StatementBusinessSegmentsAxis = us-gaap_AllOtherSegmentsMember	208,028us-gaap_NetInvestmentIncome / us-gaap_StatementBusinessSegmentsAxis = us-gaap_AllOtherSegmentsMember	165,725us-gaap_NetInvestmentIncome / us-gaap_StatementBusinessSegmentsAxis = us-gaap_AllOtherSegmentsMember
Net foreign exchange gains									6,260us-gaap_ForeignCurrencyTransactionGainLossBeforeTax / us-gaap_StatementBusinessSegmentsAxis = us-gaap_AllOtherSegmentsMember	1,917us-gaap_ForeignCurrencyTransactionGainLossBeforeTax / us-gaap_StatementBusinessSegmentsAxis = us-gaap_AllOtherSegmentsMember	5,319us-gaap_ForeignCurrencyTransactionGainLossBeforeTax / us-gaap_StatementBusinessSegmentsAxis = us-gaap_AllOtherSegmentsMember
Equity in earnings of other ventures									26,075us-gaap_IncomeLossFromEquityMethodInvestments / us-gaap_StatementBusinessSegmentsAxis = us-gaap_AllOtherSegmentsMember	23,194us-gaap_IncomeLossFromEquityMethodInvestments / us-gaap_StatementBusinessSegmentsAxis = us-gaap_AllOtherSegmentsMember	23,238us-gaap_IncomeLossFromEquityMethodInvestments / us-gaap_StatementBusinessSegmentsAxis = us-gaap_AllOtherSegmentsMember
Other loss									(423)us-gaap_OtherOperatingIncomeExpenseNet / us-gaap_StatementBusinessSegmentsAxis = us-gaap_AllOtherSegmentsMember	(2,359)us-gaap_OtherOperatingIncomeExpenseNet / us-gaap_StatementBusinessSegmentsAxis = us-gaap_AllOtherSegmentsMember	(2,120)us-gaap_OtherOperatingIncomeExpenseNet / us-gaap_StatementBusinessSegmentsAxis = us-gaap_AllOtherSegmentsMember
Net realized and unrealized gains on investments									41,433us-gaap_GainLossOnInvestments / us-gaap_StatementBusinessSegmentsAxis = us-gaap_AllOtherSegmentsMember	35,076us-gaap_GainLossOnInvestments / us-gaap_StatementBusinessSegmentsAxis = us-gaap_AllOtherSegmentsMember	163,121us-gaap_GainLossOnInvestments / us-gaap_StatementBusinessSegmentsAxis = us-gaap_AllOtherSegmentsMember
Net other-than-temporary impairments recognized in earnings											(343)us-gaap_OtherThanTemporaryImpairmentLossesInvestmentsPortionRecognizedInEarningsNetAvailableforsaleSecurities / us-gaap_StatementBusinessSegmentsAxis = us-gaap_AllOtherSegmentsMember
Corporate expenses									(22,987)us-gaap_GeneralAndAdministrativeExpense / us-gaap_StatementBusinessSegmentsAxis = us-gaap_AllOtherSegmentsMember	(33,622)us-gaap_GeneralAndAdministrativeExpense / us-gaap_StatementBusinessSegmentsAxis = us-gaap_AllOtherSegmentsMember	(16,456)us-gaap_GeneralAndAdministrativeExpense / us-gaap_StatementBusinessSegmentsAxis = us-gaap_AllOtherSegmentsMember
Interest expense									(17,164)us-gaap_InterestExpense / us-gaap_StatementBusinessSegmentsAxis = us-gaap_AllOtherSegmentsMember	(17,929)us-gaap_InterestExpense / us-gaap_StatementBusinessSegmentsAxis = us-gaap_AllOtherSegmentsMember	(23,097)us-gaap_InterestExpense / us-gaap_StatementBusinessSegmentsAxis = us-gaap_AllOtherSegmentsMember
Income tax (expense) benefit									(608)us-gaap_IncomeTaxExpenseBenefit / us-gaap_StatementBusinessSegmentsAxis = us-gaap_AllOtherSegmentsMember	(1,692)us-gaap_IncomeTaxExpenseBenefit / us-gaap_StatementBusinessSegmentsAxis = us-gaap_AllOtherSegmentsMember	(1,413)us-gaap_IncomeTaxExpenseBenefit / us-gaap_StatementBusinessSegmentsAxis = us-gaap_AllOtherSegmentsMember
Income (loss) from discontinued operations										2,422us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTax / us-gaap_StatementBusinessSegmentsAxis = us-gaap_AllOtherSegmentsMember	(16,476)us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTax / us-gaap_StatementBusinessSegmentsAxis = us-gaap_AllOtherSegmentsMember
Net income attributable to noncontrolling interests									(153,538)us-gaap_NetIncomeLossAttributableToNoncontrollingInterest / us-gaap_StatementBusinessSegmentsAxis = us-gaap_AllOtherSegmentsMember	(151,144)us-gaap_NetIncomeLossAttributableToNoncontrollingInterest / us-gaap_StatementBusinessSegmentsAxis = us-gaap_AllOtherSegmentsMember	(148,040)us-gaap_NetIncomeLossAttributableToNoncontrollingInterest / us-gaap_StatementBusinessSegmentsAxis = us-gaap_AllOtherSegmentsMember
Dividends on preference shares									(22,381)us-gaap_DividendsPreferredStock / us-gaap_StatementBusinessSegmentsAxis = us-gaap_AllOtherSegmentsMember	(24,948)us-gaap_DividendsPreferredStock / us-gaap_StatementBusinessSegmentsAxis = us-gaap_AllOtherSegmentsMember	(34,895)us-gaap_DividendsPreferredStock / us-gaap_StatementBusinessSegmentsAxis = us-gaap_AllOtherSegmentsMember
Net claims and claim expenses incurred - current accident year									0us-gaap_SupplementalInformationForPropertyCasualtyInsuranceUnderwritersCurrentYearClaimsAndClaimsAdjustmentExpense / us-gaap_StatementBusinessSegmentsAxis = us-gaap_AllOtherSegmentsMember	0us-gaap_SupplementalInformationForPropertyCasualtyInsuranceUnderwritersCurrentYearClaimsAndClaimsAdjustmentExpense / us-gaap_StatementBusinessSegmentsAxis = us-gaap_AllOtherSegmentsMember	0us-gaap_SupplementalInformationForPropertyCasualtyInsuranceUnderwritersCurrentYearClaimsAndClaimsAdjustmentExpense / us-gaap_StatementBusinessSegmentsAxis = us-gaap_AllOtherSegmentsMember
Net claims and claim expenses incurred – prior accident years									(6,137)us-gaap_SupplementalInformationForPropertyCasualtyInsuranceUnderwritersPriorYearClaimsAndClaimsAdjustmentExpense / us-gaap_StatementBusinessSegmentsAxis = us-gaap_AllOtherSegmentsMember	450us-gaap_SupplementalInformationForPropertyCasualtyInsuranceUnderwritersPriorYearClaimsAndClaimsAdjustmentExpense / us-gaap_StatementBusinessSegmentsAxis = us-gaap_AllOtherSegmentsMember	2,947us-gaap_SupplementalInformationForPropertyCasualtyInsuranceUnderwritersPriorYearClaimsAndClaimsAdjustmentExpense / us-gaap_StatementBusinessSegmentsAxis = us-gaap_AllOtherSegmentsMember
Total net incurred									(6,137)us-gaap_LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseIncurredClaims1 / us-gaap_StatementBusinessSegmentsAxis = us-gaap_AllOtherSegmentsMember	450us-gaap_LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseIncurredClaims1 / us-gaap_StatementBusinessSegmentsAxis = us-gaap_AllOtherSegmentsMember	2,947us-gaap_LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseIncurredClaims1 / us-gaap_StatementBusinessSegmentsAxis = us-gaap_AllOtherSegmentsMember
Net claims and claim expense ratio - current accident year									0.00%rnr_NetClaimsAndClaimsExpenseRatioCurrentYear / us-gaap_StatementBusinessSegmentsAxis = us-gaap_AllOtherSegmentsMember	0.00%rnr_NetClaimsAndClaimsExpenseRatioCurrentYear / us-gaap_StatementBusinessSegmentsAxis = us-gaap_AllOtherSegmentsMember	0.00%rnr_NetClaimsAndClaimsExpenseRatioCurrentYear / us-gaap_StatementBusinessSegmentsAxis = us-gaap_AllOtherSegmentsMember
Net claims and claim expense ratio - prior accident years									(1667.70%)rnr_NetClaimsAndClaimExpenseRatioPriorYears / us-gaap_StatementBusinessSegmentsAxis = us-gaap_AllOtherSegmentsMember	76.80%rnr_NetClaimsAndClaimExpenseRatioPriorYears / us-gaap_StatementBusinessSegmentsAxis = us-gaap_AllOtherSegmentsMember	(8186.10%)rnr_NetClaimsAndClaimExpenseRatioPriorYears / us-gaap_StatementBusinessSegmentsAxis = us-gaap_AllOtherSegmentsMember
Net claims and claim expense ratio - calendar year									(1667.70%)us-gaap_LossRatio / us-gaap_StatementBusinessSegmentsAxis = us-gaap_AllOtherSegmentsMember	76.80%us-gaap_LossRatio / us-gaap_StatementBusinessSegmentsAxis = us-gaap_AllOtherSegmentsMember	(8186.10%)us-gaap_LossRatio / us-gaap_StatementBusinessSegmentsAxis = us-gaap_AllOtherSegmentsMember
Underwriting expense ratio									(1697.00%)us-gaap_UnderwritingExpenseRatio / us-gaap_StatementBusinessSegmentsAxis = us-gaap_AllOtherSegmentsMember	108.20%us-gaap_UnderwritingExpenseRatio / us-gaap_StatementBusinessSegmentsAxis = us-gaap_AllOtherSegmentsMember	(2008.30%)us-gaap_UnderwritingExpenseRatio / us-gaap_StatementBusinessSegmentsAxis = us-gaap_AllOtherSegmentsMember
Combined ratio									(3364.70%)us-gaap_CombinedRatio / us-gaap_StatementBusinessSegmentsAxis = us-gaap_AllOtherSegmentsMember	185.00%us-gaap_CombinedRatio / us-gaap_StatementBusinessSegmentsAxis = us-gaap_AllOtherSegmentsMember	(10194.40%)us-gaap_CombinedRatio / us-gaap_StatementBusinessSegmentsAxis = us-gaap_AllOtherSegmentsMember
Intersegment Eliminations
Segment Reporting Information [Line Items]
Gross premiums written									$ 300us-gaap_PremiumsWrittenGross / us-gaap_StatementBusinessSegmentsAxis = us-gaap_IntersegmentEliminationMember	$ (1,000)us-gaap_PremiumsWrittenGross / us-gaap_StatementBusinessSegmentsAxis = us-gaap_IntersegmentEliminationMember	$ (500)us-gaap_PremiumsWrittenGross / us-gaap_StatementBusinessSegmentsAxis = us-gaap_IntersegmentEliminationMember

X

- Definition

Net claims and claim expense ratio - prior accident years is derived by dividing net claims and claim expenses - prior accident years by net premiums earned.

+ References

No definition available.

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Net claims and claim expense ratio - current accident year is derived by dividing net claims and claim expense - current accident year by net premiums earned.

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Net premiums earned less net claims and claim expenses incurred, acquisition expenses and operational expenses directly related to underwriting activities.

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No definition available.

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X

- Definition

Ratio of non-life losses and loss expenses, non-life acquisition expenses and non-life general and administrative expenses, to non-life net premiums earned.

+ References

No definition available.

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X

- Definition

Amount of expense related to deferred policy acquisition costs.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 16

-Article 12



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Amount of paid and unpaid preferred stock dividends declared with the form of settlement in cash, stock and payment-in-kind (PIK).

+ References

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-Name Regulation S-X (SX)

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Amount before tax of foreign currency transaction realized and unrealized gain (loss) recognized in the income statement.

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