Commitments and Contingencies - Firm Commitments and Options to Purchase Aircraft (Details)	Mar. 31, 2023 commitment aircraft
787
Long-term Purchase Commitment [Line Items]
Number of Firm Commitments | commitment	100
Scheduled Aircraft Deliveries
Last Nine Months of 2023	0
2024	8
After 2024	92
737 MAX
Long-term Purchase Commitment [Line Items]
Number of Firm Commitments | commitment	412
Scheduled Aircraft Deliveries
Last Nine Months of 2023	114
2024	88
After 2024	210
A321neo
Long-term Purchase Commitment [Line Items]
Number of Firm Commitments | commitment	70
Scheduled Aircraft Deliveries
Last Nine Months of 2023	12
2024	31
After 2024	27
A321XLR
Long-term Purchase Commitment [Line Items]
Number of Firm Commitments | commitment	50
Scheduled Aircraft Deliveries
Last Nine Months of 2023	0
2024	0
After 2024	50
A350
Long-term Purchase Commitment [Line Items]
Number of Firm Commitments | commitment	45
Scheduled Aircraft Deliveries
Last Nine Months of 2023	0
2024	0
After 2024	45