v2.4.0.6

Investments Investments (Reverse Purchase Agreements) (Details) (USD $) In Millions, unless otherwise specified	Mar. 31, 2013	Dec. 31, 2012
Investments, Debt and Equity Securities [Abstract]
Value of reverse repurchase agreements	$ 118.2	$ 74.8
Minimum required collateral for reverse repurchase agreemetns, expressed as a percentage of loan principal	102.00%

X

- Definition

Securities Purchased Under Agreements To Resell Required Collateral Percentage Of Principal

+ References

No definition available.

+ Details

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Namespace Prefix:	rnr_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

X

- Details

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X

- Definition

The carrying value of securities purchased to be resold in reverse repurchase transactions as of the balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.4-08.(m)(2)(i))

-URI http://asc.fasb.org/extlink&oid=6881521&loc=d3e23780-122690

+ Details

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Balance Type:	debit
Period Type:	instant