v2.4.0.6

Investments (Narrative) (Details) (USD $)	3 Months Ended
	Mar. 31, 2012		Mar. 31, 2011
Investment [Line Items]
Cash and investments at fair value on deposit with, or in trust accounts for the benefit of various counterparties	$ 1,252,100,000
Cash and investments at fair value on deposit with, or in trust accounts for the benefit of, U.S. state regulatory authorities	483,000,000
Portion of other-than-temporary impairments recognized in other comprehensive income	27,000	[1]	0	[1]
Net other-than-temporary impairments recognized in earnings	134,000		0
Recognized Due To Intent To Sell Securities [Member]
Investment [Line Items]
Portion of other-than-temporary impairments recognized in other comprehensive income	0		0
Recognized Due To Required Sales Of Securities [Member]
Investment [Line Items]
Portion of other-than-temporary impairments recognized in other comprehensive income	$ 0		$ 0
[1] Includes all other subsidiaries of RenaissanceRe Holdings Ltd. and eliminations.

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Carrying amount of cash and investment securities on deposit with state regulatory authorities in connection with capital requirements.

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The total amount of cash and securities held by third party trustees pursuant to terms of debt instruments or other agreements as of the date of each statement of financial position presented, which can be used by the trustee only to pay the noncurrent portion of specified obligations.

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The amount of other than temporary impairment (OTTI) loss on a debt security, categorized as Available-for-sale, related to factors other than credit losses when the entity does not intend to sell the security and it is not more likely than not that the entity will be required to sell the security before recovery of its amortized cost basis. This amount, which includes the portion attributable to the noncontrolling interest, if any, is a portion of the deduction from the total impairment losses of investments (before taxes) presented on the income statement; this amount is also referred to as the amount incurred by the reporting entity or the consolidated entity.

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The amount of other than temporary impairment losses on investments in debt and equity securities categorized as Available-for-sale which have been recognized in earnings during the period. Such impairment losses consist of other than temporary impairments (OTTI) on equity securities, credit losses on investments in debt securities, and when the entity intends to sell an impaired debt security or it is more likely than not that the entity will be required to sell the impaired debt security before recovery of its amortized cost basis.

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