REVENUE FROM CONTRACTS WITH CUSTOMERS (Tables)

12 Months Ended

Dec. 31, 2018

Revenue from Contracts with Customer [Abstract]

Disaggregation of Revenue [Table Text Block]

Passenger revenue recognized in the consolidated statements of operations (in millions):

	Twelve Months Ended December 31,
	2018		2017		2016
Passenger ticket revenue, including ticket breakage and net of taxes and fees	$	6,483	$	6,246	$	4,568
Passenger ancillary revenue	530		514		381
Mileage PlanTM passenger revenue	619		541		443
Total passenger revenue	$	7,632	$	7,301	$	5,392

Mileage Plan™ revenue included in the consolidated statements of operations (in millions):

	Twelve Months Ended December 31,
	2018		2017		2016
Passenger revenue	$	619	$	541	$	443
Mileage PlanTM other revenue	434		418		370
Total Mileage Plan™ revenue	$	1,053	$	959	$	813

Cargo and other revenue included in the consolidated statements of operations (in millions):

	Twelve Months Ended December 31,
	2018		2017		2016
Cargo revenue	$	128	$	115	$	108
Other revenue	70		60		55
Total Cargo and other revenue	$	198	$	175	$	163

Contract with Customer, Asset and Liability [Table Text Block]

The table below presents a roll forward of the total frequent flyer liability (in millions):

	Twelve Months Ended December 31,
	2018			2017
Total Deferred Revenue balance at January 1	$	1,725		$	1,534
Travel miles and companion certificate redemption - Passenger revenue	(619		)	(541		)
Miles redeemed on partner airlines - Other revenue	(90		)	(73		)
Increase in liability for mileage credits issued	858			805
Total Deferred Revenue balance at December 31	$	1,874		$	1,725