Preferred Stock, Amount of Preferred Dividends in Arrears, Equivalent Number of Periods, Trigger

No definition available.

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- Definition

Preferred Stock, Preferred Stock Dividends in Arrears, Triggered Shareholder Election Right, Number of Directors

+ References

No definition available.

+ Details

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- Definition

The maximum number of common shares and nonredeemable preferred shares (or preferred stock redeemable solely at the option of the issuer) permitted to be issued by an entity's charter and bylaws.

+ References

No definition available.

+ Details

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- Definition

Amount of decrease in additional paid in capital (APIC) resulting from direct costs associated with issuing stock. Includes, but is not limited to, legal and accounting fees and direct costs associated with stock issues under a shelf registration.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section 50

-Paragraph 2

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-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.3-04)

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- Definition

Aggregate dividends paid during the period for each share of common stock outstanding.

+ References

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- Definition

Aggregate dividends declared during the period for each share of common stock outstanding.

+ References

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- Definition

The maximum number of common shares permitted to be issued by an entity's charter and bylaws.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.29)

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 30

-Article 5

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- Definition

Amount of paid and unpaid common stock dividends declared with the form of settlement in cash, stock and payment-in-kind (PIK).

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Article 3

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-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.3-04)

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-Topic 942

-SubTopic 405

-Section 45

-Paragraph 2

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+ Details

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- Definition

Amount of paid and unpaid preferred stock dividends declared with the form of settlement in cash, stock and payment-in-kind (PIK).

+ References

+ Details

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- Definition

The percentage rate used to calculate dividend payments on preferred stock.

+ References

No definition available.

+ Details

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- Definition

Face amount or stated value per share of preferred stock nonredeemable or redeemable solely at the option of the issuer.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.28)

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-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 29

-Article 5

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- Definition

The redemption (or callable) amount of currently redeemable preferred stock. Includes amounts representing dividends not currently declared or paid but which will be payable under the redemption features or for which ultimate payment is solely within the control of the issuer.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section 50

-Paragraph 11

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-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.27(b))

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+ Details

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- Definition

The price per share at which the preferred stock of an entity that has priority over common stock in the distribution of dividends and in the event of liquidation of the entity is redeemed or may be called at. The redemption features of this preferred stock are solely within the control of the issuer.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section 50

-Paragraph 3

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-Topic 505

-SubTopic 10

-Section 50

-Paragraph 5

-Subparagraph (a)

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+ Details

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- Definition

The maximum number of nonredeemable preferred shares (or preferred stock redeemable solely at the option of the issuer) permitted to be issued by an entity's charter and bylaws.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.28)

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 29

-Article 5

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- Definition

Aggregate share number for all nonredeemable preferred stock (or preferred stock redeemable solely at the option of the issuer) held by stockholders. Does not include preferred shares that have been repurchased.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.28)

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 29

-Article 5

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- Definition

Proceeds from issuance of capital stock which provides for a specific dividend that is paid to the shareholders before any dividends to common stockholders and which takes precedence over common stockholders in the event of liquidation.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Financing Activities

-URI http://asc.fasb.org/extlink&oid=6513228

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-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 14

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3255-108585

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Balance Type:	debit
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- Definition

Number of new stock issued during the period.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Article 3

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section 50

-Paragraph 2

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.3-04)

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 29, 30

-Article 5

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Period Type:	duration

- Definition

Number of stock bought back by the entity at the exercise price or redemption price.

+ References

+ Details

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Period Type:	duration

- Definition

Number of shares that have been repurchased during the period and have not been retired and are not held in treasury. Some state laws may govern the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.

+ References

+ Details

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- Definition

Equity impact of the value of stock that has been repurchased during the period and has not been retired and is not held in treasury. Some state laws may mandate the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.

+ References

+ Details

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- Definition

Amount of stock repurchase plan authorized.

+ References

No definition available.

+ Details

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- Definition

Amount remaining of a stock repurchase plan authorized.

+ References

No definition available.

+ Details

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- Definition

Total cost of shares repurchased divided by the total number of shares repurchased.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 30

-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6405813&loc=d3e23239-112655

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Shareholders' Equity (Narrative) (Details) (USD $)	1 Months Ended	3 Months Ended								12 Months Ended			0 Months Ended					1 Months Ended	0 Months Ended	1 Months Ended
Shareholders' Equity (Narrative) (Details) (USD $)	May 31, 2013	Dec. 31, 2014 director period	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014 director period	Dec. 31, 2013	Dec. 31, 2012	Dec. 15, 2014	Sep. 15, 2014	Jun. 13, 2014	Mar. 14, 2014	Jun. 27, 2013	Mar. 31, 2004	Dec. 27, 2012	Dec. 31, 2006	Nov. 13, 2014	Mar. 23, 2009
Class of Stock [Line Items]
Aggregate authorized shares		325,000,000rnr_StockSharesAuthorized								325,000,000rnr_StockSharesAuthorized
Authorized common shares		225,000,000us-gaap_CommonStockSharesAuthorized								225,000,000us-gaap_CommonStockSharesAuthorized
Authorized preference shares		100,000,000us-gaap_PreferredStockSharesAuthorized								100,000,000us-gaap_PreferredStockSharesAuthorized
Dividends declared, Per common share										$ 1.16	$ 1.12	$ 1.08
Preference Shares, Par Value (In dollars per share)		$ 1				$ 1				$ 1	$ 1
Preference shares, Issuance costs	$ 9,144,000
Preference shares, Shares outstanding		16,000,000us-gaap_PreferredStockSharesOutstanding				16,000,000us-gaap_PreferredStockSharesOutstanding				16,000,000us-gaap_PreferredStockSharesOutstanding	16,000,000us-gaap_PreferredStockSharesOutstanding
Preference shares, Amount of preferred dividends in arrears, equivalent number of periods, trigger		6								6
Preference shares, Preferred stock dividends in arrears, triggered shareholder election right, number of directors		2								2
Preference shares, Dividends declared and paid		5,595,000us-gaap_DividendsPreferredStock	5,595,000us-gaap_DividendsPreferredStock	5,596,000us-gaap_DividendsPreferredStock	5,595,000us-gaap_DividendsPreferredStock	5,595,000us-gaap_DividendsPreferredStock	5,595,000us-gaap_DividendsPreferredStock	7,483,000us-gaap_DividendsPreferredStock	6,275,000us-gaap_DividendsPreferredStock	22,381,000us-gaap_DividendsPreferredStock	24,948,000us-gaap_DividendsPreferredStock	34,895,000us-gaap_DividendsPreferredStock
Common stock
Class of Stock [Line Items]
Repurchase of shares										5,355,000	2,451,000	6,399,000
Common shares repurchased during period, Aggregate value										(5,355,000)	(2,451,000)	(6,399,000)
Retained earnings
Class of Stock [Line Items]
Dividends, Common Stock										45,912,000	49,267,000	53,356,000
Common shares repurchased during period, Aggregate value										(497,175,000)	(203,703,000)	(460,647,000)
Preference shares, Dividends declared and paid										22,381,000	24,948,000	34,895,000
Common stock
Class of Stock [Line Items]
Dividends declared, Per common share													$ 0.29	$ 0.29	$ 0.29	$ 0.29
Dividends paid, Per common share													$ 0.29	$ 0.29	$ 0.29	$ 0.29
Repurchase of shares										5,400,000
Common shares repurchased during period, Aggregate value										(514,200,000)
Common shares repurchased during period, Average cost per share										$ 96.04
Share repurchase program, Authorized aggregate amount																					500,000,000
Remaining authorized shares per share repurchase program		500,000,000								500,000,000
Series C Preferred Stock
Class of Stock [Line Items]
Preference shares, issued																		250,000,000
Preference shares, Shares issued																		10,000,000
Preference Shares, Par Value (In dollars per share)																		$ 25
Preference shares, Shares redeemed	5,000,000																5,000,000
Preference shares, Redemption amount																	125,000,000
Preference shares, Shares outstanding																	5,000,000
Preference shares, Redemption price per share																						$ 25
Preference shares, Dividend rate										6.08%
Series D Preferred Stock
Class of Stock [Line Items]
Preference shares, issued																				300,000,000
Preference shares, Shares issued																				12,000,000
Preference Shares, Par Value (In dollars per share)																				$ 25
Preference shares, Shares redeemed	6,000,000																6,000,000		6,000,000
Preference shares, Redemption amount																	150,000,000		150,000,000
Preference shares, Shares outstanding																	0		6,000,000
Series E Preferred Stock
Class of Stock [Line Items]
Preference shares, issued	$ 275,000,000									$ 0	$ 265,856,000	$ 0
Preference shares, Shares issued	11,000,000
Preference Shares, Par Value (In dollars per share)	$ 25
Preference shares, Redemption price per share		$ 25								$ 25
Preference shares, Dividend rate										5.375%