Noncontrolling Interests (Schedule of Redeemable Noncontrolling Interest) (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Activity in redeemable noncontrolling interest
Beginning balance	$ 3,071,308
Net (loss) income attributable to redeemable noncontrolling interest	98,091	$ 70,222
Ending balance	3,231,846
DaVinciRe Holdings Ltd.
Activity in redeemable noncontrolling interest
Beginning balance	1,435,581	1,034,946
Redemption of shares from redeemable noncontrolling interest, net of adjustments	2,607	(234)
Sale of shares to redeemable noncontrolling interests	9,991	0
Net (loss) income attributable to redeemable noncontrolling interest	84,906	62,533
Ending balance	1,533,085	1,097,245
RenaissanceRe Medici Fund Ltd.
Activity in redeemable noncontrolling interest
Beginning balance	632,112	416,765
Redemption of shares from redeemable noncontrolling interest, net of adjustments	(4,764)	(15,884)
Sale of shares to redeemable noncontrolling interests	54,613	3,596
Net (loss) income attributable to redeemable noncontrolling interest	(4,678)	2,481
Ending balance	677,283	406,958
Vermeer Reinsurance Ltd.
Activity in redeemable noncontrolling interest
Beginning balance	1,003,615	599,989
Net (loss) income attributable to redeemable noncontrolling interest	17,863	5,208
Ending balance	$ 1,021,478	$ 605,197

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Decrease in noncontrolling interest (for example, but not limited to, redeeming or purchasing the interests of noncontrolling shareholders, issuance of shares (interests) by the non-wholly owned subsidiary to the parent entity for other than cash, and a buyback of shares (interest) by the non-wholly owned subsidiary from the noncontrolling interests).

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Amount of Net Income (Loss) attributable to redeemable noncontrolling interest.

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Amount of increase in noncontrolling interest from subsidiary issuance of equity interests to noncontrolling interest holders.

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As of the reporting date, the aggregate carrying amount of all noncontrolling interests which are redeemable by the (parent) entity (1) at a fixed or determinable price on a fixed or determinable date, (2) at the option of the holder of the noncontrolling interest, or (3) upon occurrence of an event that is not solely within the control of the (parent) entity. This item includes noncontrolling interest holder's ownership (or holders' ownership) regardless of the type of equity interest (common, preferred, other) including all potential organizational (legal) forms of the investee entity.

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