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Total costs of sales and operating expenses for the period.

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REVENUE FROM CONTRACTS WITH CUSTOMERS - Narrative (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021	Dec. 31, 2021
Deferred Revenue Arrangement [Line Items]
Receivable	$ 658		$ 546
Costs and Expenses	1,883	$ 958
Mileage Plan Revenue [Member]
Deferred Revenue Arrangement [Line Items]
Receivable	108		$ 64
Mileage Plan Revenue [Member] \| Mileage plan other revenue [Member]
Deferred Revenue Arrangement [Line Items]
Contract liability revenue recognized	(9)	(4)
Passenger Revenue [Member]
Deferred Revenue Arrangement [Line Items]
Contract liability revenue recognized	$ 390	$ 136