Derivatives and Hedging Transactions (Details 2) - USD ($) $ in Millions	Sep. 30, 2015	Dec. 31, 2014
Asset Derivatives
Gross value of derivatives	$ 97.8	$ 75.5
Gross amounts offset in the Consolidated Balance Sheet	(13.7)	(18.1)
Net value of derivatives presented in the Consolidated Balance Sheet	84.1	57.4
Liability Derivatives
Gross value of derivatives	42.6	52.1
Gross amounts offset in the Consolidated Balance Sheet	(13.7)	(18.1)
Net value of derivatives presented in the Consolidated Balance Sheet	$ 28.9	$ 34.0

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