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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		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021	Dec. 31, 2021
Deferred Revenue Arrangement [Line Items]
Receivable	$ 401		$ 401		$ 546
Costs and Expenses	2,471	$ 978	4,354	$ 1,936
Mileage Plan Revenue [Member]
Deferred Revenue Arrangement [Line Items]
Receivable	76		76		$ 64
Mileage Plan Revenue [Member] \| Mileage plan other revenue [Member]
Deferred Revenue Arrangement [Line Items]
Contract liability revenue recognized			(26)	(17)
Passenger Revenue [Member]
Deferred Revenue Arrangement [Line Items]
Contract liability revenue recognized	$ 132	$ 36	$ 522	$ 175