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OneBeacon Pension Plan (Details) - USD ($) $ in Millions | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2016 | Jun. 30, 2015 | Jun. 30, 2016 | Jun. 30, 2015
Defined Contribution Plan Disclosure [Line Items] |  |  |  |
Other Income | $ 36.2 | $ 48.7 | $ 76.0 | $ 76.1
Pension Plan [Member] |  |  |  |
Defined Contribution Plan Disclosure [Line Items] |  |  |  |
Defined Benefit Pension Plan Liabilities, Current |  |  | 0.3 |
Defined Benefit Plan, Assets for Plan Benefits | 42.4 |  | 42.4 |
Transfer of assets | 12.0 |  | 12.0 |
OneBeacon [Member] |  |  |  |
Defined Contribution Plan Disclosure [Line Items] |  |  |  |
Other Income | 0.8 | $ (1.2) | $ 1.7 | $ (4.3)
OneBeacon [Member] | Pension Plan [Member] |  |  |  |
Defined Contribution Plan Disclosure [Line Items] |  |  |  |
Other Income | $ 0.1 |  |  |

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- Definition Reflects the sum of all other revenue and income recognized by the entity in the period not otherwise specified in the income statement. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 225 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-04.4) -URI http://asc.fasb.org/extlink&oid=6879464&loc=d3e573970-122913 + Details
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- Details
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