Quarterly report pursuant to Section 13 or 15(d)

Fair Value Measurements and Derivatives (Details)

v3.20.1
Fair Value Measurements and Derivatives (Details)
kT in Thousands, MT in Millions, $ in Millions, € in Billions
3 Months Ended
Mar. 31, 2020
EUR (€)
MT
kT
Mar. 31, 2020
USD ($)
MT
kT
Dec. 31, 2019
USD ($)
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]      
Fair value of long-term debt   $ 8,595.3 $ 6,957.8
Fair value of long-term debt in excess of carrying value   $ 156.6 $ 31.3
Fuel swaps      
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]      
Derivative maturing date Dec. 31, 2023    
Projected fuel purchases | MT 1.2 1.2  
Fuel swaps | Derivative Contracts Not Designated as Hedging Instruments      
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]      
Derivative maturing date Oct. 31, 2020    
Projected fuel purchases | kT 68 68  
Foreign currency contracts      
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]      
Notional amount of derivatives € 2.0 $ 2,200.0  
Interest Rate Swap [Member]      
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]      
Notional amount of derivatives   $ 700.0