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Fair Value of Financial Instruments (Details) - USD ($) $ in Millions | Dec. 31, 2015 | Dec. 31, 2014
--- | --- | ---
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Debt | $ 442.4 | $ 343.1
Tranzact [Member] | Tranzact Bank Facility |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Debt |  | 67.4
Tranzact [Member] | Fair value | Tranzact Bank Facility |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Debt Instrument, Fair Value Disclosure | 102.8 | 68.7
Tranzact [Member] | Carrying Value | Tranzact Bank Facility |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Debt | 102.9 | 67.4
OneBeacon | 2012 OBH Senior Notes |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Debt | 274.8 | 274.7
OneBeacon | Fair value | 2012 OBH Senior Notes |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Debt Instrument, Fair Value Disclosure | 276.4 | 286.0
OneBeacon | Carrying Value | 2012 OBH Senior Notes |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Debt | 274.8 | $ 274.7
MediaAlpha [Member] | Fair value | MediaAlpha Bank Facility [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Debt Instrument, Fair Value Disclosure | 15.0 |
MediaAlpha [Member] | Carrying Value | MediaAlpha Bank Facility [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Debt | $ 14.7 |

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- Definition Carrying amount of long-term debt, net of unamortized discount or premium, including current and noncurrent amounts. 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 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 2: 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 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03.16) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 20, 22 -Article 5 + Details
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