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Projected Capital Improvement Costs

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Amount of contractual obligation, including but not limited to, long-term debt, capital lease obligations, operating lease obligations, purchase obligations, and other commitments.

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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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Commitments and contingencies - Narrative (Details) $ in Millions	1 Months Ended	3 Months Ended
	Apr. 27, 2023 USD ($) aircraft	Mar. 31, 2023 USD ($) aircraft	Mar. 31, 2022 gate
Subsequent Event
Other Commitments [Line Items]
Construction obligation	$ 1,700
Convertible Debt
Other Commitments [Line Items]
Initial conversion ratio		0.0259909
Aircraft
Other Commitments [Line Items]
2023		$ 1,500
2022		1,600
2025		993
2026		1,400
2027		1,100
2028		1,300
Thereafter		$ 4,500
-7 Firm Orders
Other Commitments [Line Items]
Exercised \| aircraft		15
-7 Firm Orders \| Subsequent Event
Other Commitments [Line Items]
Exercised \| aircraft	11
-8 Firm Orders
Other Commitments [Line Items]
MAX aircrafts to be delivered this year \| aircraft		70
-8 Firm Orders \| Subsequent Event
Other Commitments [Line Items]
Exercised \| aircraft	8
B737-7Max \| Aircraft
Other Commitments [Line Items]
2022		$ 956
Long-term Purchase Commitment \| aircraft		46
William P. Hobby Airport
Other Commitments [Line Items]
New airport gates \| gate			7
Projected airport improvement costs		$ 250