Condensed Consolidating Financial Information Provided in Connection with Outstanding Debt of Subsidiaries (Condensed Consolidating Statement of Comprehensive Income (Loss) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Comprehensive income (loss)
Net (loss) Income	$ 25,173	$ 353,128
Change in net unrealized losses on investments, net of tax	(657)	(37)
Foreign currency translation adjustments, net of tax	932	0
Comprehensive income	25,448	353,091
Net (income) loss attributable to redeemable noncontrolling interests	(98,091)	(70,222)
Comprehensive income attributable to redeemable noncontrolling interests	(98,091)	(70,222)
Comprehensive (loss) income attributable to RenaissanceRe	(72,643)	282,869
Reportable Legal Entities | RenaissanceRe Finance Inc. (Subsidiary Issuer)
Comprehensive income (loss)
Net (loss) Income	(57,382)	16,743
Change in net unrealized losses on investments, net of tax	745	0
Foreign currency translation adjustments, net of tax	0
Comprehensive income	(56,637)	16,743
Net (income) loss attributable to redeemable noncontrolling interests	0	0
Comprehensive income attributable to redeemable noncontrolling interests	0	0
Comprehensive (loss) income attributable to RenaissanceRe	(56,637)	16,743
Reportable Legal Entities | RenaissanceRe Holdings Ltd. (Parent Guarantor)
Comprehensive income (loss)
Net (loss) Income	(72,918)	282,906
Change in net unrealized losses on investments, net of tax	(657)	0
Foreign currency translation adjustments, net of tax	932
Comprehensive income	(72,643)	282,906
Net (income) loss attributable to redeemable noncontrolling interests	0	0
Comprehensive income attributable to redeemable noncontrolling interests	0	0
Comprehensive (loss) income attributable to RenaissanceRe	(72,643)	282,906
Reportable Legal Entities | Other RenaissanceRe Holdings Ltd. Subsidiaries and Eliminations (Non-Guarantor Subsidiaries)
Comprehensive income (loss)
Net (loss) Income	99,196	402,922
Change in net unrealized losses on investments, net of tax	(14,562)	(37)
Foreign currency translation adjustments, net of tax
Comprehensive income	84,634	402,885
Net (income) loss attributable to redeemable noncontrolling interests	(98,091)	(70,222)
Comprehensive income attributable to redeemable noncontrolling interests	(98,091)	(70,222)
Comprehensive (loss) income attributable to RenaissanceRe	(13,457)	332,663
Consolidating Adjustments
Comprehensive income (loss)
Net (loss) Income	56,277	(349,443)
Change in net unrealized losses on investments, net of tax	13,817	0
Foreign currency translation adjustments, net of tax	0
Comprehensive income	70,094	(349,443)
Net (income) loss attributable to redeemable noncontrolling interests	0	0
Comprehensive income attributable to redeemable noncontrolling interests	0	0
Comprehensive (loss) income attributable to RenaissanceRe	$ 70,094	$ (349,443)