Changes in Components of Other Comprehensive Income (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Other Comprehensive Income [Abstract]
Pension and OPEB liability adjustments, pre-tax	$ (0.9)	$ 1.2
Unrealized gain (loss) on financial instruments, net of realized gain (loss), pre-tax	(10.5)	3.8
Unrealized foreign currency translation adjustments, pre-tax	(48.7)	(1.7)
Total other comprehensive income (loss), pre-tax	(60.1)	3.3
Pension and OPEB liability adjustments, Tax	0.3	(0.4)
Unrealized gain (loss) on financial instruments, net of realized gain (loss), Tax	0.4	0.5
Unrealized foreign currency translation adjustments, Tax	0	0
Total other comprehensive income (loss), Tax	0.7us-gaap_OtherComprehensiveIncomeLossTax	0.1us-gaap_OtherComprehensiveIncomeLossTax
Pension and OPEB liability adjustments, Net of Tax	(0.6)	0.8
Unrealized gain (loss) on financial instruments, net of realized gain (loss), Net of Tax	(10.1)	4.3
Unrealized foreign currency translation adjustments, Net of Tax	(48.7)	(1.7)
Other Comprehensive (Loss) Income	$ (59.4)	$ 3.4

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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 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 and reclassification adjustments, 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 of tax expense (benefit), after reclassification adjustments, 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 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 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 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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