Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 12
-Section 13
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Accumulated change, net of tax, in accumulated gains and losses from derivative instruments designated and qualifying as the effective portion of cash flow hedges. Includes an entity's share of an equity investee's Increase or Decrease in deferred hedging gains or losses.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Fair value of the assets less the liabilities of a derivative or group of derivatives.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Fair value as of the balance sheet date of interest rate derivative assets, net of interest rate derivative liabilities, which includes all such derivative instruments in hedging and nonhedging relationships that are recognized on the balance sheet.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Number of interest rate derivative instruments held by the entity at the reporting date.

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Significant Accounting Policies (Details 8) € in Millions, ¥ in Millions, $ in Millions	Mar. 31, 2015 USD ($) DerivativeInstrument	Mar. 31, 2015 JPY (¥) DerivativeInstrument	Dec. 31, 2014 USD ($) DerivativeInstrument	Dec. 31, 2014 JPY (¥) DerivativeInstrument	Sep. 30, 2014 EUR (€)
Derivative financial instruments
Gross accumulated other comprehensive income or loss related to derivative activities	$ 33.1		$ 45.8
Interest rate swap
Derivative financial instruments
Number of Instruments \| DerivativeInstrument	2	2	2	2
Notional Amount	$ 375.0		$ 375.0
Interest rate net, fair value			(1.2)
Interest rate swap \| Other liabilities.
Derivative financial instruments
Interest rate net, fair value	(12.3)		(2.1)
Interest rate swap \| Deferred costs and other assets
Derivative financial instruments
Interest rate net, fair value			0.9
USD-Yen currency forward contract
Derivative financial instruments
Notional Amount \| ¥		¥ 1,900.0		¥ 14.7
USD-Yen currency forward contract \| Deferred costs and other assets
Derivative financial instruments
Forward contract net, fair value	0.3		0.1
USD-Euro currency forward contract
Derivative financial instruments
Notional Amount \| €					€ 150.0
USD-Euro currency forward contract \| Deferred costs and other assets
Derivative financial instruments
Forward contract net, fair value	$ 39.8		$ 19.1