Segment Reporting - Schedule of Significant Components of the Company's Revenues and Expenses (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Segment Reporting Information [Line Items]
Gross premiums written (Note 6)	$ 9,213,540	$ 7,833,798	$ 5,806,165
Net premiums written	7,196,160	5,939,375	4,096,333
Net premiums earned	6,333,989	5,194,181	3,952,462
Net claims and claim expenses incurred	4,338,840	3,876,087	2,924,609
Acquisition expenses	1,568,606	1,214,858	897,677
Operational expenses	276,691	212,184	206,687
Underwriting income (loss)	149,852	(108,948)	(76,511)
Net investment income	559,932	319,479	354,038
Net foreign exchange gains (losses)	(56,909)	(41,006)	27,773
Equity in earnings (losses) of other ventures	11,249	12,309	17,194
Other income (loss)	12,636	10,880	213
Net realized and unrealized gains (losses) on investments	(1,800,485)	(218,134)	820,636
Corporate expenses	(46,775)	(41,152)	(96,970)
Interest expense	(48,335)	(47,536)	(50,453)
Income (loss) before taxes	(1,218,835)	(114,108)	995,920
Income tax benefit (expense)	59,019	10,668	(2,862)
Net (income) loss attributable to redeemable noncontrolling interests	98,613	63,285	(230,653)
Dividends on preference shares	(35,375)	(33,266)	(30,923)
Net income (loss) available (attributable) to RenaissanceRe common shareholders	(1,096,578)	(73,421)	731,482
Net claims and claim expenses incurred – current accident year	4,586,422	4,125,557	3,108,421
Net claims and claim expenses incurred – prior accident years	(247,582)	(249,470)	(183,812)
Total net incurred	$ 4,338,840	$ 3,876,087	$ 2,924,609
Net claims and claim expense ratio – current accident year	72.40%	79.40%	78.60%
Net claims and claim expense ratio – prior accident years	(3.90%)	(4.80%)	(4.60%)
Net claims and claim expense ratio – calendar year	68.50%	74.60%	74.00%
Underwriting expense ratio	29.20%	27.50%	27.90%
Combined ratio	97.70%	102.10%	101.90%
Other
Segment Reporting Information [Line Items]
Gross premiums written (Note 6)	$ 0	$ 0	$ 0
Net premiums written	0	0	0
Net premiums earned	0	0	0
Net claims and claim expenses incurred	0	0	0
Acquisition expenses	0	0	0
Operational expenses	0	0	0
Underwriting income (loss)	0	0	0
Net investment income	559,932	319,479	354,038
Net foreign exchange gains (losses)	(56,909)	(41,006)	27,773
Equity in earnings (losses) of other ventures	11,249	12,309	17,194
Other income (loss)	12,636	10,880	213
Net realized and unrealized gains (losses) on investments	(1,800,485)	(218,134)	820,636
Corporate expenses	(46,775)	(41,152)	(96,970)
Interest expense	(48,335)	(47,536)	(50,453)
Income tax benefit (expense)	59,019	10,668	(2,862)
Net (income) loss attributable to redeemable noncontrolling interests	98,613	63,285	(230,653)
Dividends on preference shares	(35,375)	(33,266)	(30,923)
Net claims and claim expenses incurred – current accident year	0	0	0
Net claims and claim expenses incurred – prior accident years	0	0	0
Total net incurred	0	0	0
Property
Segment Reporting Information [Line Items]
Gross premiums written (Note 6)	3,734,241	3,958,724	2,999,142
Net claims and claim expenses incurred – prior accident years	(205,741)	(233,373)	(157,049)
Property | Operating Segments
Segment Reporting Information [Line Items]
Gross premiums written (Note 6)	3,734,241	3,958,724	2,999,142
Net premiums written	2,847,659	2,868,002	2,037,200
Net premiums earned	2,770,227	2,608,298	1,936,215
Net claims and claim expenses incurred	2,044,771	2,163,016	1,435,947
Acquisition expenses	547,210	487,178	353,700
Operational expenses	194,355	143,608	135,547
Underwriting income (loss)	(16,109)	(185,504)	11,021
Net claims and claim expenses incurred – current accident year	2,250,512	2,396,389	1,592,996
Net claims and claim expenses incurred – prior accident years	(205,741)	(233,373)	(157,049)
Total net incurred	$ 2,044,771	$ 2,163,016	$ 1,435,947
Net claims and claim expense ratio – current accident year	81.20%	91.90%	82.30%
Net claims and claim expense ratio – prior accident years	(7.40%)	(9.00%)	(8.10%)
Net claims and claim expense ratio – calendar year	73.80%	82.90%	74.20%
Underwriting expense ratio	26.80%	24.20%	25.20%
Combined ratio	100.60%	107.10%	99.40%
Casualty and Specialty
Segment Reporting Information [Line Items]
Gross premiums written (Note 6)	$ 5,479,299	$ 3,875,074	$ 2,807,023
Net claims and claim expenses incurred – prior accident years	(41,841)	(16,097)	(26,763)
Casualty and Specialty | Operating Segments
Segment Reporting Information [Line Items]
Gross premiums written (Note 6)	5,479,299	3,875,074	2,807,023
Net premiums written	4,348,501	3,071,373	2,059,133
Net premiums earned	3,563,762	2,585,883	2,016,247
Net claims and claim expenses incurred	2,294,069	1,713,071	1,488,662
Acquisition expenses	1,021,396	727,680	543,977
Operational expenses	82,336	68,576	71,140
Underwriting income (loss)	165,961	76,556	(87,532)
Net claims and claim expenses incurred – current accident year	2,335,910	1,729,168	1,515,425
Net claims and claim expenses incurred – prior accident years	(41,841)	(16,097)	(26,763)
Total net incurred	$ 2,294,069	$ 1,713,071	$ 1,488,662
Net claims and claim expense ratio – current accident year	65.50%	66.90%	75.20%
Net claims and claim expense ratio – prior accident years	(1.10%)	(0.70%)	(1.40%)
Net claims and claim expense ratio – calendar year	64.40%	66.20%	73.80%
Underwriting expense ratio	30.90%	30.80%	30.50%
Combined ratio	95.30%	97.00%	104.30%