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Amount of commitment classified as other to be paid after fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of commitment classified as other to be paid in fourth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of commitment classified as other to be paid in third fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Commitments and contingencies - Narrative (Details) $ in Millions			1 Months Ended
	Sep. 28, 2021 USD ($)	Jun. 30, 2021 USD ($)	May 02, 2022 aircraft	Apr. 30, 2022 USD ($)	Mar. 31, 2022 USD ($) aircraft
Other Commitments [Line Items]
Decrease in operating lease liability		$ 343
Aircrafts to be purchased \| aircraft					632
Leaseholds and Leasehold Improvements
Other Commitments [Line Items]
Construction payments		$ 343
Subsequent Event \| Capital Addition Purchase Commitments
Other Commitments [Line Items]
2022				$ 689
2023				$ 188
Cash Capital Commitments, Boeing Orders
Other Commitments [Line Items]
Remainder of 2022					$ 2,100
2023					1,900
2024					1,000
2025					839
2026					975
2027					1,000
Thereafter					6,000
Payment Guarantee, Dallas Love Field Series 2010 Bonds
Other Commitments [Line Items]
Principal amount of guarantee					79
Net present value of future principal and interest payments					$ 89
-8 Firm Orders
Other Commitments [Line Items]
Aircrafts to be purchased \| aircraft					145
-8 Firm Orders \| Subsequent Event
Other Commitments [Line Items]
Converted, 2022 \| aircraft			1
Exercised, 2022 \| aircraft			16
Exercised, 2023 \| aircraft			10
-7 Firm Orders
Other Commitments [Line Items]
Aircrafts to be purchased \| aircraft					276
-7 Firm Orders \| Subsequent Event
Other Commitments [Line Items]
Converted, 2022 \| aircraft			40
Converted, 2023 \| aircraft			1
Exercised, 2023 \| aircraft			2
Shifted, 2023 \| aircraft			10
B-737-8 MAX
Other Commitments [Line Items]
Aircrafts to be purchased \| aircraft					15
B737-7Max
Other Commitments [Line Items]
Aircrafts to be purchased \| aircraft					12
Love Field Airport Modernization Corporation \| Series 2010 Bonds
Other Commitments [Line Items]
Debt redeemed	$ 310
Interest expense	$ 7