Condensed Consolidated Statements of Comprehensive Income (Loss) (USD $) In Millions, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Statement of Comprehensive Income [Abstract]
Net Income	$ 13.5us-gaap_ProfitLoss	$ 35.1us-gaap_ProfitLoss
Other Comprehensive Income Before Income Taxes:
Unrealized Holding Gains	53.3	120.0
Foreign Currency Translation Adjustments	(0.9)	0
Amortization of Unrecognized Postretirement Benefit Costs	5.4	2.0
Other Comprehensive Income Before Income Taxes	57.8	122.0
Other Comprehensive Income Tax Expense	(20.2)us-gaap_OtherComprehensiveIncomeLossTax	(43.1)us-gaap_OtherComprehensiveIncomeLossTax
Other Comprehensive Income	37.6	78.9
Total Comprehensive Income	$ 51.1	$ 114.0

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income. Excludes changes in equity resulting from investments by owners and distributions to owners.

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Amount before tax, after reclassification adjustments, of appreciation (loss) in value of unsold available-for-sale securities. Excludes amounts related to other than temporary impairment (OTTI) loss.

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Amount before tax, after reclassification adjustments of other comprehensive income (loss).

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Amount before tax, after reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature.

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Amount after tax and reclassification adjustments of other comprehensive income (loss).

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Amount before tax, after reclassification adjustments, of (increase) decrease in accumulated other comprehensive (income) loss related to pension and other postretirement defined benefit plans.

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Amount of tax expense (benefit) allocated to other comprehensive income (loss).

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The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.

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