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Discontinued Operations Discontinued Operations (Fair Value) (Details) $ in Millions	Dec. 31, 2015 USD ($)
Sirius Group | SIG Senior Notes | Fair value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt	$ 410.0
Sirius Group | SIG Senior Notes | Carrying Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt	399.8
Sirius Group | SIG Preference Shares | Fair value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt	255.0
Sirius Group | SIG Preference Shares | Carrying Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt	250.0
Tranzact | Tranzact Bank Facility [Member] | Fair value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt	102.8
Tranzact | Tranzact Bank Facility [Member] | Carrying Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt	$ 102.9

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+ References

No definition available.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(16))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

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(16))
-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 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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