Commitments and Contingencies - Firm Commitments and Options to Purchase Aircraft (Details)	Sep. 30, 2023 aircraft_commitment aircraft
787
Long-term Purchase Commitment [Line Items]
Number of Firm Commitments \| aircraft_commitment	150
Number Of Aircrafts Expected To Take Delivery [Abstract]
Last Three Months of 2023	0
2024	8
After 2024	142
Last Three Months of 2023	0
2024	8
After 2024	142
737 MAX
Long-term Purchase Commitment [Line Items]
Number of Firm Commitments \| aircraft_commitment	374
Number Of Aircrafts Expected To Take Delivery [Abstract]
Last Three Months of 2023	73
2024	100
After 2024	201
Last Three Months of 2023	20
2024	77
After 2024	277
A321neo
Long-term Purchase Commitment [Line Items]
Number of Firm Commitments \| aircraft_commitment	130
Number Of Aircrafts Expected To Take Delivery [Abstract]
Last Three Months of 2023	4
2024	26
After 2024	100
Last Three Months of 2023	4
2024	26
After 2024	100
A321XLR
Long-term Purchase Commitment [Line Items]
Number of Firm Commitments \| aircraft_commitment	50
Number Of Aircrafts Expected To Take Delivery [Abstract]
Last Three Months of 2023	0
2024	0
After 2024	50
Last Three Months of 2023	0
2024	0
After 2024	50
A350
Long-term Purchase Commitment [Line Items]
Number of Firm Commitments \| aircraft_commitment	45
Number Of Aircrafts Expected To Take Delivery [Abstract]
Last Three Months of 2023	0
2024	0
After 2024	45
Last Three Months of 2023	0
2024	0
After 2024	45

Number Of Aircraft To Be Delivered Under the Contract, Remainder of Year

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Number Of Aircraft To Be Delivered Under the Contract, Thereafter

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Number Of Aircraft To Be Delivered Under the Contract, Year One

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Number Of Aircrafts Expected To Take Delivery [Abstract]

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Number Of Aircrafts Expected To Take Delivery, Remainder Of Year

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Number Of Aircrafts Expected To Take Delivery, Thereafter

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Number Of Aircrafts Expected To Take Delivery, Year One

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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The minimum number of units that must be purchased, in connection with an unconditional purchase obligation that has not been recognized for financial reporting purposes.

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