Schedule II. Condensed Financial Information Of Registrant (Statements of Operations) (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
Revenues
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)	5,036	2,392	(1,061)	1,747	488	(932)	614	6,260	1,917	5,319
Other income (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
Total revenues	318,798us-gaap_Revenues	266,496us-gaap_Revenues	331,174us-gaap_Revenues	343,609us-gaap_Revenues	405,209us-gaap_Revenues	391,572us-gaap_Revenues	250,235us-gaap_Revenues	333,466us-gaap_Revenues	1,260,077us-gaap_Revenues	1,380,482us-gaap_Revenues	1,424,295us-gaap_Revenues
Expenses
Interest expense	4,289us-gaap_InterestExpense	4,290us-gaap_InterestExpense	4,292us-gaap_InterestExpense	4,293us-gaap_InterestExpense	4,297us-gaap_InterestExpense	4,298us-gaap_InterestExpense	4,300us-gaap_InterestExpense	5,034us-gaap_InterestExpense	17,164us-gaap_InterestExpense	17,929us-gaap_InterestExpense	23,097us-gaap_InterestExpense
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
Operating and corporate expenses	10,583us-gaap_GeneralAndAdministrativeExpense	3,905us-gaap_GeneralAndAdministrativeExpense	3,954us-gaap_GeneralAndAdministrativeExpense	4,545us-gaap_GeneralAndAdministrativeExpense	3,304us-gaap_GeneralAndAdministrativeExpense	4,307us-gaap_GeneralAndAdministrativeExpense	21,529us-gaap_GeneralAndAdministrativeExpense	4,482us-gaap_GeneralAndAdministrativeExpense	22,987us-gaap_GeneralAndAdministrativeExpense	33,622us-gaap_GeneralAndAdministrativeExpense	16,456us-gaap_GeneralAndAdministrativeExpense
Total expenses	97,820us-gaap_BenefitsLossesAndExpenses	162,364us-gaap_BenefitsLossesAndExpenses	168,952us-gaap_BenefitsLossesAndExpenses	144,077us-gaap_BenefitsLossesAndExpenses	75,431us-gaap_BenefitsLossesAndExpenses	151,904us-gaap_BenefitsLossesAndExpenses	204,347us-gaap_BenefitsLossesAndExpenses	107,762us-gaap_BenefitsLossesAndExpenses	573,213us-gaap_BenefitsLossesAndExpenses	539,444us-gaap_BenefitsLossesAndExpenses	657,457us-gaap_BenefitsLossesAndExpenses
Income (loss) before equity in net income (loss) of subsidiaries and taxes									686,864	841,038	766,838
Equity in net income (loss) of subsidiaries									0	0	0
Net income attributable to RenaissanceRe	176,362us-gaap_NetIncomeLoss	73,410us-gaap_NetIncomeLoss	126,348us-gaap_NetIncomeLoss	156,598us-gaap_NetIncomeLoss	274,251us-gaap_NetIncomeLoss	185,335us-gaap_NetIncomeLoss	34,289us-gaap_NetIncomeLoss	196,749us-gaap_NetIncomeLoss	532,718us-gaap_NetIncomeLoss	690,624us-gaap_NetIncomeLoss	600,909us-gaap_NetIncomeLoss
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	170,767	67,815	120,752	151,003	268,656	179,740	26,806	190,474	510,337	665,676	566,014
Parent Company
Revenues
Net investment income									2,706	4,213	14,195
Net foreign exchange gains									(13)	(7)	33
Other income (loss)									0	106	2,822
Net realized and unrealized gains on investments									83	(483)	14,862
Total revenues									2,776	3,829	31,912
Expenses
Interest expense									0	734	5,875
Operational expenses									(4,890)	(4,962)	(5,103)
Operating and corporate expenses									20,787	31,264	14,282
Total expenses									15,897	27,036	15,054
Income (loss) before equity in net income (loss) of subsidiaries and taxes									(13,121)	(23,207)	16,858
Equity in net income (loss) of subsidiaries									545,839	713,831	584,051
Net income attributable to RenaissanceRe									532,718	690,624	600,909
Dividends on preference shares									(22,381)	(24,948)	(34,895)
Net income available to RenaissanceRe common shareholders									$ 510,337	$ 665,676	$ 566,014

The total amount of expense recognized during the period for future policy benefits, claims and claims adjustment costs, and for selling, general and administrative costs.

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