DERIVATIVE INSTRUMENTS (Tables)

12 Months Ended

Dec. 31, 2020

Derivative Instruments and Hedging Activities Disclosure [Abstract]

Schedule of Derivative Instruments in Statement of Financial Position, Fair Value [Table Text Block]

Fair values of derivative instruments on the consolidated balance sheet (in millions):

	2020		2019
Fuel hedge contracts (not designated as hedges)
Prepaid expenses and other current assets	$	11	$	8
Other assets	4		3
Interest rate swaps (designated as hedges)
Prepaid expenses and other current assets	—		1
Other noncurrent assets	—		2
Other accrued liabilities	(10)		(5)
Other liabilities	(15)		(5)
Losses in accumulated other comprehensive loss (AOCL)	(21)		(13)

Schedule of Derivative Instruments, Gain (Loss) in Statement of Financial Performance [Table Text Block]

Pretax effect of derivative instruments on earnings and AOCL (in millions):

	2020		2019		2018
Fuel hedge contracts (not designated as hedges)
Gains (losses) recognized in Aircraft fuel	$	(10)	$	(10)	$	1
Interest rate swaps (designated as hedges)
Losses recognized in Aircraft rent	(3)		(3)		(3)
Gains (losses) recognized in other comprehensive income (OCI)	(21)		(13)		—