Financial Derivative Instruments - Fuel Hedging (Details) gal in Millions	12 Months Ended
Dec. 31, 2021 gal
2022
Volume of Fuel Hedging
Fuel Hedged (in gallons)	1,220
2023
Volume of Fuel Hedging
Fuel Hedged (in gallons)	769
2024
Volume of Fuel Hedging
Fuel Hedged (in gallons)	358

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