Quarterly report pursuant to Section 13 or 15(d)

Fair Value Measurements and Derivatives (Detail Textuals)

v2.4.0.8
Fair Value Measurements and Derivatives (Detail Textuals)
In Millions, unless otherwise specified
3 Months Ended
Jun. 30, 2014
USD ($)
Dec. 31, 2013
USD ($)
Jun. 30, 2014
Fuel Swaps
Metric_ton
Jun. 30, 2014
Fuel Swaps
Maximum
Jun. 30, 2014
Fuel Collars and Fuel Options
Maximum
Metric_ton
Jun. 30, 2014
Interest Rate Swap
USD ($)
Jun. 30, 2014
Foreign Exchange Forward
USD ($)
Jun. 30, 2014
Foreign Exchange Forward
EUR (€)
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]                
Derivative maturing date       Dec. 31, 2016 Dec. 31, 2014      
Projected fuel purchases     656,000   17,000      
Notional amount of derivatives           $ 654.0 $ 27.4 € 20.0
Fair value of long-term debt 3,626.1 3,146.4            
Fair value of long-term debt in excess of carrying value $ 123.9 $ 18.6