Consolidated Statement of Comprehensive Income (USD $) In Millions, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Net Income	$ 230.7us-gaap_NetIncomeLoss	$ 181.4us-gaap_NetIncomeLoss
Other Comprehensive Income (Loss) (Net of Tax and Reclassifications)
Net Unrealized Gains on Securities Available for Sale	54.1	4.5
Net Unrealized Gains (Losses) on Cash Flow Hedges	(1.1)	1.6
Foreign Currency Translation Adjustments	(5.9)	(1.3)
Pension and Other Postretirement Benefit Adjustments	6.2	3.4
Other Comprehensive Income (Loss)	53.3	8.2
Comprehensive Income	$ 284.0us-gaap_ComprehensiveIncomeNetOfTax	$ 189.6us-gaap_ComprehensiveIncomeNetOfTax

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

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Amount after tax and 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 after tax and 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 after tax of increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss).

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Amount after tax, before reclassification adjustments, of unrealized holding gain (loss) on available-for-sale securities.

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