Reclassifications from Accumulated Other Comprehensive Income - Schedule of Accumulated Other Comprehensive Income Reclassification (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Available for sale securities:
(Loss) from operations before income tax	$ (30.6)	$ (263.0)	$ (12.4)	$ (86.7)
General, administrative and corporate expenses	160.4	110.9	391.6	352.1
Income tax credit/(expense)	15.5	9.2	13.4	5.2
Net (loss)/income	(15.1)	(253.8)	1.0	(81.5)
Reclassification out of AOCI
Available for sale securities:
Net (loss)/income	(2.4)	1.8	(2.9)	4.3
Reclassification out of AOCI \| Available for sale securities
Available for sale securities:
Realized gains on sale of securities	0.8	2.6	5.4	8.2
Realized (losses) on sale of securities	(1.1)	(1.6)	(8.9)	(5.4)
(Loss) from operations before income tax	(0.3)	1.0	(3.5)	2.8
Income tax credit/(expense)	0.1	(0.2)	0.4	(0.4)
Net (loss)/income	(0.2)	0.8	(3.1)	2.4
Reclassification out of AOCI \| Realized derivatives
Available for sale securities:
General, administrative and corporate expenses	(2.7)	1.2	0.3	2.4
Income tax credit/(expense)	0.5	(0.2)	(0.1)	(0.5)
Net (loss)/income	$ (2.2)	$ 1.0	$ 0.2	$ 1.9

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This item represents the gross profit realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities.

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Amount of income (loss) from continuing operations before deduction of income tax expense (benefit) and income (loss) attributable to noncontrolling interest, and addition of income (loss) from equity method investments.

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Amount, before tax, of income (loss) including portion attributable to noncontrolling interest. Includes, but is not limited to, income (loss) from continuing operations, discontinued operations and equity method investments.

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Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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The aggregate total costs related to selling a firm's product and services, as well as all other general and administrative expenses. Direct selling expenses (for example, credit, warranty, and advertising) are expenses that can be directly linked to the sale of specific products. Indirect selling expenses are expenses that cannot be directly linked to the sale of specific products, for example telephone expenses, Internet, and postal charges. General and administrative expenses include salaries of non-sales personnel, rent, utilities, communication, etc.

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