Annual report pursuant to Section 13 and 15(d)

Fair Value Measurements and Derivatives (Textuals) (Details)

v3.19.3.a.u2
Fair Value Measurements and Derivatives (Textuals) (Details)
T in Millions, $ in Millions, € in Billions
12 Months Ended
Dec. 31, 2019
EUR (€)
T
Dec. 31, 2019
USD ($)
T
Dec. 31, 2018
USD ($)
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]      
Fair value of long-term debt   $ 6,957.8 $ 6,601.9
Fair value of long-term debt in excess of carrying value   $ 31.3 $ 8.4
Fuel swaps      
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]      
Derivative maturing date Dec. 31, 2022    
Projected fuel purchases | T 1.1 1.1  
Foreign currency contracts      
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]      
Notional amount of derivatives € 1.8 $ 2,000.0  
Interest rate contracts      
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]      
Notional amount of derivatives   $ 1,700.0