DEBT AND CREDIT FACILITIES - Schedule of Debt Obligations (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Jun. 05, 2023	Dec. 31, 2022
Debt Instrument [Line Items]
Long-term debt	$ 1,800,000		$ 1,100,000
Fair value
Debt Instrument [Line Items]
Long-term debt	1,771,820		1,110,649
Carrying value
Debt Instrument [Line Items]
Long-term debt	1,882,893		1,170,442
Senior Notes | Fair value
Debt Instrument [Line Items]
Long-term debt	1,771,820		1,080,649
Senior Notes | Carrying value
Debt Instrument [Line Items]
Long-term debt	$ 1,882,893		1,140,442
Senior Notes | 5.750% Senior Notes due 2033
Debt Instrument [Line Items]
Stated interest rate	5.75%	5.75%
Senior Notes | 5.750% Senior Notes due 2033 | RenaissanceRe Finance, Inc. | Fair value
Debt Instrument [Line Items]
Long-term debt	$ 707,633		0
Senior Notes | 5.750% Senior Notes due 2033 | RenaissanceRe Finance, Inc. | Carrying value
Debt Instrument [Line Items]
Long-term debt	$ 740,887		0
Senior Notes | 3.600% Senior Notes due 2029
Debt Instrument [Line Items]
Stated interest rate	3.60%
Senior Notes | 3.600% Senior Notes due 2029 | RenaissanceRe Finance, Inc. | Fair value
Debt Instrument [Line Items]
Long-term debt	$ 351,760		362,644
Senior Notes | 3.600% Senior Notes due 2029 | RenaissanceRe Finance, Inc. | Carrying value
Debt Instrument [Line Items]
Long-term debt	$ 394,906		394,221
Senior Notes | 3.450% Senior Notes due 2027
Debt Instrument [Line Items]
Stated interest rate	3.45%
Senior Notes | 3.450% Senior Notes due 2027 | RenaissanceRe Finance, Inc. | Fair value
Debt Instrument [Line Items]
Long-term debt	$ 276,381		280,506
Senior Notes | 3.450% Senior Notes due 2027 | RenaissanceRe Finance, Inc. | Carrying value
Debt Instrument [Line Items]
Long-term debt	$ 298,146		297,775
Senior Notes | 3.700% Senior Notes due 2025
Debt Instrument [Line Items]
Stated interest rate	3.70%
Senior Notes | 3.700% Senior Notes due 2025 | RenaissanceRe Finance, Inc. | Fair value
Debt Instrument [Line Items]
Long-term debt	$ 290,454		290,874
Senior Notes | 3.700% Senior Notes due 2025 | RenaissanceRe Finance, Inc. | Carrying value
Debt Instrument [Line Items]
Long-term debt	$ 299,444		299,168
Senior Notes | 4.750% Senior Notes due 2025 (DaVinci) | DaVinci Holdings Ltd.
Debt Instrument [Line Items]
Stated interest rate	4.75%
Senior Notes | 4.750% Senior Notes due 2025 (DaVinci) | DaVinci Holdings Ltd. | Fair value
Debt Instrument [Line Items]
Long-term debt	$ 145,592		146,625
Senior Notes | 4.750% Senior Notes due 2025 (DaVinci) | DaVinci Holdings Ltd. | Carrying value
Debt Instrument [Line Items]
Long-term debt	149,510		149,278
Line of Credit | Medici Revolving Credit Facility | Fair value
Debt Instrument [Line Items]
Long-term debt	0		30,000
Line of Credit | Medici Revolving Credit Facility | Carrying value
Debt Instrument [Line Items]
Long-term debt	$ 0		$ 30,000