Derivatives and Fair Value Measurements (Details 3) - USD ($) $ in Millions	Sep. 30, 2015	Dec. 31, 2014
Fair value of financial asset (liability) positions measured on a recurring basis
Investments in debt and equity securities	$ 50.9	$ 61.8
Foreign currency forward contract [Member]
Fair value of financial asset (liability) positions measured on a recurring basis
Derivative assets (liabilities), at fair value, net	(293.5)
Diesel fuel hedge contracts [Member]
Fair value of financial asset (liability) positions measured on a recurring basis
Derivative assets (liabilities), at fair value, net	(106.7)
Fair Value, Measurements, Recurring [Member]
Fair value of financial asset (liability) positions measured on a recurring basis
Investments in debt and equity securities	50.9	61.8
Total net financial assets (liabilities)	(349.3)	(515.3)
Fair Value, Measurements, Recurring [Member] | Commodity swap contracts [Member]
Fair value of financial asset (liability) positions measured on a recurring basis
Derivative assets (liabilities), at fair value, net	(106.7)	(167.1)
Fair Value, Measurements, Recurring [Member] | Foreign currency forward contract [Member]
Fair value of financial asset (liability) positions measured on a recurring basis
Derivative assets (liabilities), at fair value, net	(293.5)	(410.0)
Fair Value, Measurements, Recurring [Member] | Level 1 [Member]
Fair value of financial asset (liability) positions measured on a recurring basis
Investments in debt and equity securities	20.2	26.1
Total net financial assets (liabilities)	20.2	26.1
Fair Value, Measurements, Recurring [Member] | Level 1 [Member] | Commodity swap contracts [Member]
Fair value of financial asset (liability) positions measured on a recurring basis
Derivative assets (liabilities), at fair value, net	0.0	0.0
Fair Value, Measurements, Recurring [Member] | Level 1 [Member] | Foreign currency forward contract [Member]
Fair value of financial asset (liability) positions measured on a recurring basis
Derivative assets (liabilities), at fair value, net	0.0	0.0
Fair Value, Measurements, Recurring [Member] | Level 2 [Member]
Fair value of financial asset (liability) positions measured on a recurring basis
Investments in debt and equity securities	30.7	35.7
Total net financial assets (liabilities)	30.7	(541.4)
Fair Value, Measurements, Recurring [Member] | Level 2 [Member] | Commodity swap contracts [Member]
Fair value of financial asset (liability) positions measured on a recurring basis
Derivative assets (liabilities), at fair value, net	0.0	(167.1)
Fair Value, Measurements, Recurring [Member] | Level 2 [Member] | Foreign currency forward contract [Member]
Fair value of financial asset (liability) positions measured on a recurring basis
Derivative assets (liabilities), at fair value, net	0.0	(410.0)
Fair Value, Measurements, Recurring [Member] | Level 3 [Member]
Fair value of financial asset (liability) positions measured on a recurring basis
Investments in debt and equity securities	0.0	0.0
Total net financial assets (liabilities)	(400.2)	0.0
Fair Value, Measurements, Recurring [Member] | Level 3 [Member] | Commodity swap contracts [Member]
Fair value of financial asset (liability) positions measured on a recurring basis
Derivative assets (liabilities), at fair value, net	(106.7)	0.0
Fair Value, Measurements, Recurring [Member] | Level 3 [Member] | Foreign currency forward contract [Member]
Fair value of financial asset (liability) positions measured on a recurring basis
Derivative assets (liabilities), at fair value, net	$ (293.5)	$ 0.0