Name:	rnr_TradingSecuritiesDebtMaturitiesAfterFiveThroughTenYearsAmortizedCostBasis
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This item represents the fair value of debt securities which are expected to mature after five through ten years of the balance sheet date and are categorized as trading securities.

No definition available.

Name:	rnr_TradingSecuritiesDebtMaturitiesAfterFiveThroughTenYearsFairValue
Namespace Prefix:	rnr_
Data Type:	xbrli:monetaryItemType
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This item represents debt securities, at cost, net of adjustments including accretion, amortization and collection of cash, if any, which are expected to mature within one year of the balance sheet date and are categorized as trading securities.

No definition available.

Name:	rnr_TradingSecuritiesDebtMaturitiesAfterOneThroughFiveYearsAmortizedCostBasis
Namespace Prefix:	rnr_
Data Type:	xbrli:monetaryItemType
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This item represents the fair value of debt securities which are expected to mature after one through five years of the balance sheet date and are categorized as trading securities.

No definition available.

Name:	rnr_TradingSecuritiesDebtMaturitiesAfterOneThroughFiveYearsFairValue
Namespace Prefix:	rnr_
Data Type:	xbrli:monetaryItemType
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This item represents debt securities, at cost, net of adjustments including accretion, amortization and collection of cash, if any, which are expected to mature after ten years of the balance sheet date and are categorized as trading securities.

No definition available.

Name:	rnr_TradingSecuritiesDebtMaturitiesAfterTenYearsAmortizedCostBasis
Namespace Prefix:	rnr_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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This item represents the fair value of debt securities which are expected to mature after ten years of the balance sheet date and are categorized as trading securities.

No definition available.

Name:	rnr_TradingSecuritiesDebtMaturitiesAfterTenYearsFairValue
Namespace Prefix:	rnr_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

No definition available.

Name:	rnr_TradingSecuritiesDebtMaturitiesWithinOneYearAmortizedCostBasis
Namespace Prefix:	rnr_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

This item represents the fair value of debt securities which are expected to mature within one year of the balance sheet date and are categorized as trading securities.

No definition available.

Name:	rnr_TradingSecuritiesDebtMaturitiesWithinOneYearFairValue
Namespace Prefix:	rnr_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

Amount of investments in debt and equity securities and other forms of securities that provide ownership interests classified as trading.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=82896770&loc=d3e26626-111562

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.4)
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=82896770&loc=d3e26610-111562

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Data Type:	xbrli:monetaryItemType
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Period Type:	instant

- References

No definition available.

Name:	us-gaap_TradingSecuritiesAbstract
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Amortized cost of investments in debt securities classified as trading.

No definition available.