Commitments and Contingencies - Aircraft and Engine Orders (Details)	12 Months Ended
Dec. 31, 2023 aircraft engine
Air Transportation Equipment
Long-term Purchase Commitment [Line Items]
2024	23
2025	42
2026	41
2027	42
2028	40
Thereafter	22
Total	210
Aircraft Engine
Long-term Purchase Commitment [Line Items]
2024 \| engine	2
2025 \| engine	4
2026 \| engine	4
2027 \| engine	3
2028 \| engine	2
Thereafter \| engine	0
Total \| engine	15
A320neo \| Air Transportation Equipment
Long-term Purchase Commitment [Line Items]
2024	0
2025	17
2026	19
2027	21
2028	10
Thereafter	0
Total	67
A321neo \| Air Transportation Equipment
Long-term Purchase Commitment [Line Items]
2024	23
2025	25
2026	22
2027	21
2028	30
Thereafter	22
Total	143

Long-term Purchase Commitment, Minimum Quantity Required, After Year Five

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Long-term Purchase Commitment, Minimum Quantity Required, Year Five

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Long-term Purchase Commitment, Minimum Quantity Required, Year Four

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Long-term Purchase Commitment, Minimum Quantity Required, Year One

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Long-term Purchase Commitment, Minimum Quantity Required, Year Three

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Long-term Purchase Commitment, Minimum Quantity Required, Year Two

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Number of units of goods that must be purchased within the specified time period of the agreement to avoid penalties or unfavorable effects on pricing, among other adverse consequences.

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