The amount the liability recorded for the income tax examination increased or decreased in the current year/accounting period.

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The amount of the additional liability or refund received or expected based on a final settlement with a taxing authority.

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The total amount of unrecognized tax benefits that, if recognized, would affect the effective tax rate.

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-Paragraph 15A
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Income Tax Examination, Increase (Decrease) in Liability from Prior Year, Dissallowed

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Income Taxes (Tax Examinations) (Details) - USD ($) $ in Millions	Mar. 31, 2016	Dec. 31, 2015	Mar. 31, 2014
Income Tax Examination [Line Items]
Unrecognized tax benefit recognition including interest and penalties, if recognized, would effect income tax expense		$ 13.6	$ 5.0
Tax Assessment Year 2005 to 2006 [Member] \| IRS
Income Tax Examination [Line Items]
Tax Examination		3.3
Tax Assessment Year 2007 to 2009 [Member] \| IRS
Income Tax Examination [Line Items]
Tax Examination		4.0
Income Tax Examination, Increase (Decrease) in Liability from Prior Year, Dissallowed		2.7
OneBeacon
Income Tax Examination [Line Items]
Income Tax Examination, Liability (Refund) Adjustment from Settlement with Taxing Authority		$ 1.1
Scenario, Forecast [Member]
Income Tax Examination [Line Items]
Unrecognized tax benefit recognition including interest and penalties, if recognized, would effect income tax expense	$ 12.0