Noncontrolling Interests (Schedule Of Redeemable Noncontrolling Interest) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Activity in redeemable noncontrolling interest
Balance, Beginning	$ 1,045,964
Net income attributable to redeemable noncontrolling interest	127,086	$ 111,050	$ 153,538
Balance, Ending	1,175,594	1,045,964
DaVinciRe Holdings Ltd.
Activity in redeemable noncontrolling interest
Balance, Beginning	930,955	1,037,306
Redemption of shares from redeemable noncontrolling interests	(98,285)	(212,750)
Sale of shares to redeemable noncontrolling interest	43,040	0
Net income attributable to redeemable noncontrolling interest	118,748	106,399	149,817
Balance, Ending	994,458	930,955	1,037,306
RenaissanceRe Medici Fund Ltd.
Activity in redeemable noncontrolling interest
Balance, Beginning	115,009	94,402
Redemption of shares from redeemable noncontrolling interests	(21,729)	(20,117)
Sale of shares to redeemable noncontrolling interest	79,518	36,073
Net income attributable to redeemable noncontrolling interest	8,338	4,651	3,721
Balance, Ending	$ 181,136	$ 115,009	$ 94,402

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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- Definition

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).

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
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- Definition

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

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-Name Accounting Standards Codification
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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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