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Financial Derivative Instruments - Fuel Hedging (Details)
gal in Millions
6 Months Ended
Jun. 30, 2022
gal
Remainder of 2022  
Volume of Fuel Hedging  
Fuel Hedged (in gallons) 610
2023  
Volume of Fuel Hedging  
Fuel Hedged (in gallons) 769
2024  
Volume of Fuel Hedging  
Fuel Hedged (in gallons) 358