Derivative Instruments and Hedging Activities (Details Textual) (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Dec. 31, 2012	Sep. 30, 2013 Not Designated as Hedging Instrument [Member]	Dec. 31, 2012 Not Designated as Hedging Instrument [Member]	Sep. 30, 2013 Cash Flow Hedging [Member] Designated as Hedging Instrument [Member]	Dec. 31, 2012 Cash Flow Hedging [Member] Designated as Hedging Instrument [Member]
Derivative [Line Items]
Losses recognized on de-designated derivative contracts			$ 4.9
Gains included in other comprehensive income for de-designated derivative contracts			0.2
Losses in AOCI to be reclassified in 12 months	(0.4)
Cash collateral on our hedges	0.8	0.6
Derivative, Notional Amount			$ 27.3	$ 20.4	$ 27.4	$ 50.9