SEGMENT REPORTING - Schedule of Significant Components of the Company's Revenues and Expenses (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Segment Reporting Information [Line Items]
Gross premiums written	$ 2,790,261	$ 2,942,964
Net premiums written	2,263,703	2,165,217
Net premiums earned	1,680,550	1,486,425
Net claims and claim expenses incurred	801,200	841,733
Acquisition expenses	432,257	376,507
Operational expenses	77,474	67,907
Underwriting income (loss)	369,619	200,278
Net investment income	254,378	83,691
Net foreign exchange gain (loss)	(14,503)	(15,486)
Equity in earnings (losses) of other ventures	9,530	(6,390)
Other income (loss)	(4,306)	1,193
Net realized and unrealized gains (losses) on investments	279,451	(673,017)
Corporate expenses	(12,843)	(12,502)
Interest expense	(12,134)	(11,955)
Income (loss) before taxes	869,192	(434,188)
Income tax benefit (expense)	(28,902)	36,707
Net (income) loss attributable to redeemable noncontrolling interests	(267,384)	11,912
Dividends on preference shares	(8,844)	(8,844)
Net income (loss) available (attributable) to RenaissanceRe common shareholders	564,062	(394,413)
Net claims and claim expenses incurred – current accident year	905,952	859,566
Net claims and claim expenses incurred – prior accident years	(104,752)	(17,833)
Total net incurred	$ 801,200	$ 841,733
Net claims and claim expense ratio – current accident year	53.90%	57.80%
Net claims and claim expense ratio – prior accident years	(6.20%)	(1.20%)
Net claims and claim expense ratio – calendar year	47.70%	56.60%
Underwriting expense ratio	30.30%	29.90%
Combined ratio	78.00%	86.50%
Other
Segment Reporting Information [Line Items]
Gross premiums written	$ 0	$ 0
Net premiums written	0	0
Net premiums earned	0	0
Net claims and claim expenses incurred	0	0
Acquisition expenses	0	0
Operational expenses	0	0
Underwriting income (loss)	0	0
Net investment income	254,378	83,691
Net foreign exchange gain (loss)	(14,503)	(15,486)
Equity in earnings (losses) of other ventures	9,530	(6,390)
Other income (loss)	(4,306)	1,193
Net realized and unrealized gains (losses) on investments	279,451	(673,017)
Corporate expenses	(12,843)	(12,502)
Interest expense	(12,134)	(11,955)
Income tax benefit (expense)	(28,902)	36,707
Net (income) loss attributable to redeemable noncontrolling interests	(267,384)	11,912
Dividends on preference shares	(8,844)	(8,844)
Net claims and claim expenses incurred – current accident year	0	0
Net claims and claim expenses incurred – prior accident years	0	0
Total net incurred	0	0
Property
Segment Reporting Information [Line Items]
Net claims and claim expenses incurred – prior accident years	(81,693)	(16,758)
Property | Operating Segments
Segment Reporting Information [Line Items]
Gross premiums written	1,304,199	1,343,508
Net premiums written	1,019,829	890,166
Net premiums earned	687,420	618,591
Net claims and claim expenses incurred	187,609	259,761
Acquisition expenses	145,319	127,096
Operational expenses	55,813	46,932
Underwriting income (loss)	298,679	184,802
Net claims and claim expenses incurred – current accident year	269,302	276,519
Net claims and claim expenses incurred – prior accident years	(81,693)	(16,758)
Total net incurred	$ 187,609	$ 259,761
Net claims and claim expense ratio – current accident year	39.20%	44.70%
Net claims and claim expense ratio – prior accident years	(11.90%)	(2.70%)
Net claims and claim expense ratio – calendar year	27.30%	42.00%
Underwriting expense ratio	29.30%	28.10%
Combined ratio	56.60%	70.10%
Casualty and Specialty
Segment Reporting Information [Line Items]
Net claims and claim expenses incurred – prior accident years	$ (23,059)	$ (1,075)
Casualty and Specialty | Operating Segments
Segment Reporting Information [Line Items]
Gross premiums written	1,486,062	1,599,456
Net premiums written	1,243,874	1,275,051
Net premiums earned	993,130	867,834
Net claims and claim expenses incurred	613,591	581,972
Acquisition expenses	286,938	249,411
Operational expenses	21,661	20,975
Underwriting income (loss)	70,940	15,476
Net claims and claim expenses incurred – current accident year	636,650	583,047
Net claims and claim expenses incurred – prior accident years	(23,059)	(1,075)
Total net incurred	$ 613,591	$ 581,972
Net claims and claim expense ratio – current accident year	64.10%	67.20%
Net claims and claim expense ratio – prior accident years	(2.30%)	(0.10%)
Net claims and claim expense ratio – calendar year	61.80%	67.10%
Underwriting expense ratio	31.10%	31.10%
Combined ratio	92.90%	98.20%