Contractual interest rate for funds borrowed, under the debt agreement.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(16))
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
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-Section S99
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Debt and Credit Facilities (Summary of Debt Obligations) (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Jun. 29, 2017	Jun. 01, 2017	Dec. 31, 2016	May 04, 2015	Mar. 24, 2015
Debt Instrument [Line Items]
Long-term debt, fair value	$ 1,018,200			$ 964,800
Long-term debt	$ 989,623			$ 948,663
3.450% Senior Notes due 2027
Debt Instrument [Line Items]
Senior notes interest rate	3.45%
3.700% Senior Notes due 2025
Debt Instrument [Line Items]
Senior notes interest rate	3.70%
5.75% Senior Notes due 2020
Debt Instrument [Line Items]
Senior notes interest rate	5.75%
Series B 7.50% Senior Notes due 2017
Debt Instrument [Line Items]
Senior notes interest rate				7.50%
4.750% Senior Notes due 2025 (DaVinciRe)
Debt Instrument [Line Items]
Senior notes interest rate	4.75%
RenaissanceRe Finance, Inc. \| 3.700% Senior Notes due 2025
Debt Instrument [Line Items]
Senior notes interest rate						3.70%
DaVinciRe Holdings Ltd. \| 4.750% Senior Notes due 2025 (DaVinciRe)
Debt Instrument [Line Items]
Senior notes interest rate					4.75%
Senior Notes
Debt Instrument [Line Items]
Long-term debt, fair value	$ 1,018,235			$ 964,800
Long-term debt	989,623			948,663
Senior Notes \| 3.700% Senior Notes due 2025
Debt Instrument [Line Items]
Long-term debt, fair value	302,781			291,750
Long-term debt	297,318			296,948
Senior Notes \| 5.75% Senior Notes due 2020
Debt Instrument [Line Items]
Long-term debt, fair value	263,750			270,875
Long-term debt	249,272			248,941
Senior Notes \| RenaissanceRe Finance, Inc. \| 3.450% Senior Notes due 2027
Debt Instrument [Line Items]
Senior notes interest rate		3.45%
Long-term debt, fair value	294,654			0
Long-term debt	295,303			0
Senior Notes \| Platinum Underwriters Finance, Inc \| Series B 7.50% Senior Notes due 2017
Debt Instrument [Line Items]
Senior notes interest rate			7.50%
Long-term debt, fair value	0			257,500
Long-term debt	0			255,352
Senior Notes \| DaVinciRe Holdings Ltd. \| 4.750% Senior Notes due 2025 (DaVinciRe)
Debt Instrument [Line Items]
Long-term debt, fair value	157,050			144,675
Long-term debt	$ 147,730			$ 147,422