Annual report pursuant to Section 13 and 15(d)

Fair Value Measurements and Derivatives - Derivatives Measured at Fair Value and Disclosed by Balance Sheet Location (Details)

v3.20.4
Fair Value Measurements and Derivatives - Derivatives Measured at Fair Value and Disclosed by Balance Sheet Location (Details) - USD ($)
$ in Thousands
Dec. 31, 2020
Dec. 31, 2019
Derivatives, Fair Value [Line Items]    
Derivative assets, fair value $ 49,029 $ 277
Derivative liabilities, fair value 142,130 192,034
Designated as Hedging Instrument    
Derivatives, Fair Value [Line Items]    
Derivative assets, fair value 55,850 3,429
Derivative liabilities, fair value 131,864 192,034
Derivatives not Designated as Hedging Instruments    
Derivatives, Fair Value [Line Items]    
Derivative assets, fair value 546  
Derivative liabilities, fair value 10,266  
Fuel contracts | Designated as Hedging Instrument | Other long-term assets    
Derivatives, Fair Value [Line Items]    
Derivative assets, fair value   277
Fuel contracts | Designated as Hedging Instrument | Accrued expenses and other liabilities    
Derivatives, Fair Value [Line Items]    
Derivative assets, fair value   2,300
Derivative liabilities, fair value 35,973 18,257
Fuel contracts | Designated as Hedging Instrument | Other long-term liabilities    
Derivatives, Fair Value [Line Items]    
Derivative assets, fair value   683
Derivative liabilities, fair value 28,947 17,763
Fuel contracts | Derivatives not Designated as Hedging Instruments | Accrued expenses and other liabilities    
Derivatives, Fair Value [Line Items]    
Derivative assets, fair value 546  
Derivative liabilities, fair value 6,732  
Fuel contracts | Derivatives not Designated as Hedging Instruments | Other long-term liabilities    
Derivatives, Fair Value [Line Items]    
Derivative liabilities, fair value 3,534  
Foreign currency contracts | Designated as Hedging Instrument | Prepaid expenses and other assets    
Derivatives, Fair Value [Line Items]    
Derivative assets, fair value 5,779  
Foreign currency contracts | Designated as Hedging Instrument | Other long-term assets    
Derivatives, Fair Value [Line Items]    
Derivative assets, fair value 43,250  
Foreign currency contracts | Designated as Hedging Instrument | Accrued expenses and other liabilities    
Derivatives, Fair Value [Line Items]    
Derivative liabilities, fair value 14,778 33,475
Foreign currency contracts | Designated as Hedging Instrument | Other long-term liabilities    
Derivatives, Fair Value [Line Items]    
Derivative assets, fair value 6,821 169
Derivative liabilities, fair value 44,938 118,500
Interest rate contracts | Designated as Hedging Instrument | Accrued expenses and other liabilities    
Derivatives, Fair Value [Line Items]    
Derivative liabilities, fair value 6,776 2,178
Interest rate contracts | Designated as Hedging Instrument | Other long-term liabilities    
Derivatives, Fair Value [Line Items]    
Derivative liabilities, fair value 452 1,861
Total derivatives    
Derivatives, Fair Value [Line Items]    
Derivative assets, fair value 56,396 3,429
Derivative liabilities, fair value $ 142,130 $ 192,034