DEBT AND CREDIT FACILITIES - Schedule of Debt Obligations (Details) - USD ($) $ in Thousands	Jun. 30, 2025	May 01, 2025	Apr. 01, 2025	Mar. 05, 2025	Feb. 25, 2025	Dec. 31, 2024	May 04, 2015	Mar. 24, 2015
Debt Instrument [Line Items]
Long-term debt	$ 2,300,000					$ 1,900,000
Fair Value
Debt Instrument [Line Items]
Long-term debt	2,301,984					1,871,492
Carrying Value
Debt Instrument [Line Items]
Long-term debt	2,263,379					1,886,689
Senior Notes \| Fair Value
Debt Instrument [Line Items]
Long-term debt	2,266,984					1,871,492
Senior Notes \| Carrying Value
Debt Instrument [Line Items]
Long-term debt	$ 2,228,379					1,886,689
Senior Notes \| 5.950% Senior Notes due 2035 (DaVinci) \| DaVinci Holdings Ltd.
Debt Instrument [Line Items]
Stated interest rate	5.95%			5.95%
Senior Notes \| 5.950% Senior Notes due 2035 (DaVinci) \| DaVinci Holdings Ltd. \| Fair Value
Debt Instrument [Line Items]
Long-term debt	$ 301,065					0
Senior Notes \| 5.950% Senior Notes due 2035 (DaVinci) \| DaVinci Holdings Ltd. \| Carrying Value
Debt Instrument [Line Items]
Long-term debt	$ 296,859					0
Senior Notes \| 5.800% Senior Notes due 2035 \| RenaissanceRe Finance, Inc.
Debt Instrument [Line Items]
Stated interest rate	5.80%				5.80%
Senior Notes \| 5.800% Senior Notes due 2035 \| RenaissanceRe Finance, Inc. \| Fair Value
Debt Instrument [Line Items]
Long-term debt	$ 511,435					0
Senior Notes \| 5.800% Senior Notes due 2035 \| RenaissanceRe Finance, Inc. \| Carrying Value
Debt Instrument [Line Items]
Long-term debt	$ 493,466					0
Senior Notes \| 5.750% Senior Notes due 2033 \| RenaissanceRe Finance, Inc.
Debt Instrument [Line Items]
Stated interest rate	5.75%
Senior Notes \| 5.750% Senior Notes due 2033 \| RenaissanceRe Finance, Inc. \| Fair Value
Debt Instrument [Line Items]
Long-term debt	$ 771,743					755,693
Senior Notes \| 5.750% Senior Notes due 2033 \| RenaissanceRe Finance, Inc. \| Carrying Value
Debt Instrument [Line Items]
Long-term debt	$ 742,535					742,068
Senior Notes \| 3.600% Senior Notes due 2029 \| RenaissanceRe Finance, Inc.
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	$ 387,136					376,816
Senior Notes \| 3.600% Senior Notes due 2029 \| RenaissanceRe Finance, Inc. \| Carrying Value
Debt Instrument [Line Items]
Long-term debt	$ 396,508					396,051
Senior Notes \| 3.450% Senior Notes due 2027 \| RenaissanceRe Finance, Inc.
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	$ 295,605					290,070
Senior Notes \| 3.450% Senior Notes due 2027 \| RenaissanceRe Finance, Inc. \| Carrying Value
Debt Instrument [Line Items]
Long-term debt	$ 299,011					298,765
Senior Notes \| 3.700% Senior Notes due 2025 \| RenaissanceRe Finance, Inc.
Debt Instrument [Line Items]
Stated interest rate	3.70%		3.70%					3.70%
Senior Notes \| 3.700% Senior Notes due 2025 \| RenaissanceRe Finance, Inc. \| Fair Value
Debt Instrument [Line Items]
Long-term debt	$ 0					299,550
Senior Notes \| 3.700% Senior Notes due 2025 \| RenaissanceRe Finance, Inc. \| Carrying Value
Debt Instrument [Line Items]
Long-term debt	$ 0					299,908
Senior Notes \| 4.750% Senior Notes due 2025 (DaVinci) \| DaVinci Holdings Ltd.
Debt Instrument [Line Items]
Stated interest rate	4.75%			4.75%
Senior Notes \| 4.750% Senior Notes due 2025 (DaVinci) \| DaVinci Holdings Ltd. \| Fair Value
Debt Instrument [Line Items]
Long-term debt	$ 0					149,363
Senior Notes \| 4.750% Senior Notes due 2025 (DaVinci) \| DaVinci Holdings Ltd. \| Carrying Value
Debt Instrument [Line Items]
Long-term debt	0					149,897
Senior Notes \| 4.750% Senior Notes due 2025 (DaVinci) \| RenaissanceRe Finance, Inc.
Debt Instrument [Line Items]
Stated interest rate		4.75%					4.75%
Line of Credit \| Medici Revolving Credit Facility \| Fair Value \| Revolving Credit Facility
Debt Instrument [Line Items]
Long-term debt	35,000					0
Line of Credit \| Medici Revolving Credit Facility \| Carrying Value \| Revolving Credit Facility
Debt Instrument [Line Items]
Long-term debt	$ 35,000					$ 0