REVENUE RECOGNITION - Schedule of Operating Revenue by Geographic Region (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2025	Mar. 31, 2024
Disaggregation of Revenue [Line Items]
Total operating revenue	$ 13,213	$ 12,539
Domestic (U.S. and Canada)
Disaggregation of Revenue [Line Items]
Total operating revenue	8,034	7,673
Atlantic
Disaggregation of Revenue [Line Items]
Total operating revenue	1,899	1,833
Latin America
Disaggregation of Revenue [Line Items]
Total operating revenue	1,557	1,445
Pacific
Disaggregation of Revenue [Line Items]
Total operating revenue	$ 1,722	$ 1,588

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

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+ Details