Condensed Consolidating Financial Information Provided in Connection with Outstanding Debt of Subsidiaries (Condensed Consolidating Statement of Comprehensive (Loss) Income (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2013
Condensed Financial Statements, Captions [Line Items]
Net income (loss)	$ 40,340	$ 107,944	$ 448,855	$ 353,128	$ (123,986)	$ 48,829	$ 251,867	$ 92,207	$ 950,267	$ 268,917	$ (354,671)
Change in net unrealized gains on investments, net of tax									2,173	(1,657)	(909)
Foreign currency translation adjustments, net of tax									(2,679)	0	0
Comprehensive income (loss)									949,761	267,260	(355,580)
Net (income) loss attributable to redeemable noncontrolling interests									(201,469)	(41,553)	132,282
Comprehensive loss attributable to redeemable noncontrolling interests									(201,469)	(41,553)	132,282
Comprehensive income (loss) attributable to RenaissanceRe									748,292	225,707	(223,298)
RenaissanceRe Holdings Ltd. (Parent Guarantor)
Condensed Financial Statements, Captions [Line Items]
Change in net unrealized gains on investments, net of tax									2,173	(1,657)	(909)
Foreign currency translation adjustments, net of tax									(2,679)	0		$ 0
Comprehensive income (loss)									748,292	225,707	(223,298)
Net (income) loss attributable to redeemable noncontrolling interests									0	0	0
Comprehensive loss attributable to redeemable noncontrolling interests									0	0	0
Comprehensive income (loss) attributable to RenaissanceRe									748,292	225,707	(223,298)
Reportable Legal Entities | RenaissanceRe Holdings Ltd. (Parent Guarantor)
Condensed Financial Statements, Captions [Line Items]
Net income (loss)									748,798	227,364	(222,389)
Change in net unrealized gains on investments, net of tax									2,173	(1,657)	(909)
Foreign currency translation adjustments, net of tax									(2,679)
Comprehensive income (loss) attributable to RenaissanceRe									748,292	225,707	(223,298)
Reportable Legal Entities | Other RenaissanceRe Holdings Ltd. Subsidiaries And Eliminations (Non-Guarantor Subsidiaries)
Condensed Financial Statements, Captions [Line Items]
Net income (loss)									1,020,509	349,780	(285,838)
Change in net unrealized gains on investments, net of tax									0	0	0
Foreign currency translation adjustments, net of tax									0
Comprehensive income (loss)									1,020,509	349,780	(285,838)
Net (income) loss attributable to redeemable noncontrolling interests									(201,469)	(41,553)	132,282
Comprehensive loss attributable to redeemable noncontrolling interests									(201,469)	(41,553)	132,282
Comprehensive income (loss) attributable to RenaissanceRe									819,040	308,227	(153,556)
Reportable Legal Entities | RenRe North America Holdings Inc. (Subsidiary Issuer)
Condensed Financial Statements, Captions [Line Items]
Net income (loss)									24,558	3,936	(5,926)
Change in net unrealized gains on investments, net of tax									528	(160)	(89)
Foreign currency translation adjustments, net of tax									0
Comprehensive income (loss)									25,086	3,776	(6,015)
Net (income) loss attributable to redeemable noncontrolling interests									0	0	0
Comprehensive loss attributable to redeemable noncontrolling interests									0	0	0
Comprehensive income (loss) attributable to RenaissanceRe									25,086	3,776	(6,015)
Reportable Legal Entities | Platinum Underwriters Finance, Inc. (Subsidiary Issuer)
Condensed Financial Statements, Captions [Line Items]
Net income (loss)											30,596
Change in net unrealized gains on investments, net of tax											0
Comprehensive income (loss)											30,596
Net (income) loss attributable to redeemable noncontrolling interests											0
Comprehensive loss attributable to redeemable noncontrolling interests											0
Comprehensive income (loss) attributable to RenaissanceRe											30,596
Reportable Legal Entities | RenaissanceRe Finance, Inc. (Subsidiary Issuer)
Condensed Financial Statements, Captions [Line Items]
Net income (loss)									40,746	(47,395)	(38,871)
Change in net unrealized gains on investments, net of tax									764	(162)	(89)
Foreign currency translation adjustments, net of tax									0
Comprehensive income (loss)									41,510	(47,557)	(38,960)
Net (income) loss attributable to redeemable noncontrolling interests									0	0	0
Comprehensive loss attributable to redeemable noncontrolling interests									0	0	0
Comprehensive income (loss) attributable to RenaissanceRe									41,510	(47,557)	(38,960)
Consolidating Adjustments
Condensed Financial Statements, Captions [Line Items]
Net income (loss)									(884,344)	(264,768)	167,757
Change in net unrealized gains on investments, net of tax									(1,292)	322	178
Foreign currency translation adjustments, net of tax									0
Comprehensive income (loss)									(885,636)	(264,446)	167,935
Net (income) loss attributable to redeemable noncontrolling interests									0	0	0
Comprehensive loss attributable to redeemable noncontrolling interests									0	0	0
Comprehensive income (loss) attributable to RenaissanceRe									$ (885,636)	$ (264,446)	$ 167,935