v2.4.0.6

Variable Interest Entities (Details) (USD $)	3 Months Ended			5 Months Ended	3 Months Ended	1 Months Ended			5 Months Ended	3 Months Ended	1 Months Ended
	Mar. 31, 2013	Mar. 31, 2012	Mar. 31, 2013 Upsilon Re [Member]	Jun. 01, 2012 Upsilon Re [Member] Variable Interest Entity, Primary Beneficiary [Member]	Mar. 31, 2013 Upsilon Reinsurance II Ltd [Member] Variable Interest Entity, Primary Beneficiary [Member]	Jun. 30, 2012 Tim Re III [Member] Variable Interest Entity, Primary Beneficiary [Member]	Feb. 28, 2013 Nonvoting Class B Shares [Member] Upsilon Re [Member]	Mar. 31, 2013 Nonvoting Class B Shares [Member] Upsilon Re [Member]	Jun. 01, 2012 Nonvoting Class B Shares [Member] Upsilon Re [Member] Variable Interest Entity, Primary Beneficiary [Member]	Mar. 31, 2013 Nonvoting Class B Shares [Member] Upsilon Reinsurance II Ltd [Member] Variable Interest Entity, Primary Beneficiary [Member]	Jun. 30, 2012 Nonvoting Class B Shares [Member] Tim Re III [Member] Variable Interest Entity, Primary Beneficiary [Member]
Variable Interest Entity [Line Items]
Gross premiums written	$ 635,418,000	$ 664,151,000		$ 37,400,000	$ 53,500,000	$ 41,100,000
Issuance of equity to third party investors									16,800,000	61,000,000	44,800,000
Investment in variable interest entity									48,800,000	76,400,000	10,300,000
Variable interest entity, ownership percentage				74.50%	55.60%	18.60%
Increase (decrease) in funds held under Reinsurance Agreements				17,600,000		5,200,000				17,500,000
Risk participation percentage				61.40%	42.90%	17.10%
Stock Redeemed, Portion of outstanding third party non-voting Class B shares							20,500,000
Third-party non-voting Class B Shares, Outstanding								2,400,000
Guarantor obligations, Collateral returned to third parties			23,000,000
Ceded premiums written	$ 198,605,000	$ 171,576,000				$ 37,700,000

X

- Definition

Total consideration paid and payable by direct and assumed policyholders for insurance and reinsurance contracts sold by the entity during the period. This amount includes premium assumed from other insurers.

+ References

No definition available.

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- Definition

Guarantor Obligations, Collateral Released to Third Parties

+ References

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X

- Definition

Variable Interest Entity, Qualitative or Quantitative Information, Risk Participation Percentage

+ References

No definition available.

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X

- Definition

Total consideration paid and payable to reinsurers during the period pursuant to terms of reinsurance arrangements.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 17

-Article 12



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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 605

-Section 50

-Paragraph 1

-Subparagraph (b),(c)(2)

-URI http://asc.fasb.org/extlink&oid=6486672&loc=d3e27261-158547



Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 113

-Paragraph 27

-Subparagraph a, b

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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X

- Definition

Value of all classes of common stock held by shareholders. May be all or portion of the number of common shares authorized. These shares exclude common shares repurchased by the entity and held as treasury shares.

+ 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)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682



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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 30

-Article 5

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- Definition

Represents a sale (new stock issuance) by a subsidiary to noncontrolling interests (third parties, parties directly or indirectly unrelated to parent) during the period. The capital transaction by subsidiary does not result in a loss of control by the parent, but does effect a change in total (consolidated) equity attributable to the parent.

+ References

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

-Publisher AICPA

-Name Accounting Research Bulletin (ARB)

-Number 51

-Paragraph 38

-Subparagraph d

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.



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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 810

-SubTopic 10

-Section 55

-Paragraph 4M

-URI http://asc.fasb.org/extlink&oid=18733213&loc=SL4591554-111686



Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section S99

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6959260&loc=d3e187085-122770



Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher AICPA

-Name Accounting Research Bulletin (ARB)

-Number 51

-Paragraph A7

-Appendix A

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- Definition

The change in funds held under reinsurance agreements or treaty (contract between the reinsurer and the ceding entity stipulating the manner in which insurance written on various risks is to be shared).

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 95

-Paragraph 28

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.



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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=6943989&loc=d3e3602-108585

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- Definition

The cash outflow associated with the acquisition of or advances to an entity that is related to it but not strictly controlled (for example, an unconsolidated subsidiary, affiliate, and joint venture or equity method investment) or the acquisition of an additional interest in a subsidiary (controlled entity).

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 13

-Subparagraph (b)

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- Definition

Equity impact of the value of stock bought back by the entity at the exercise price or redemption price.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section 50

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21463-112644



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-Name Statement of Financial Accounting Standard (FAS)

-Number 129

-Paragraph 4, 5

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- Definition

Percentage of the Variable Interest Entity's (VIE) voting interest owned by (or beneficial interest in) the reporting entity (directly or indirectly).

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 810

-SubTopic 10

-Section 50

-Paragraph 5A

-Subparagraph (d)

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