OPERATING SEGMENT INFORMATION (DETAILS) (USD $) In Millions, unless otherwise specified	3 Months Ended				9 Months Ended
	Sep. 30, 2014		Sep. 30, 2013		Sep. 30, 2014		Sep. 30, 2013
Segment Reporting Information [Line Items]
Airline, Capacity Purchase Arrangements, Percent	100.00%				100.00%
Operating revenues
Passenger, Mainline	$ 1,030		$ 960		$ 2,858		$ 2,651
Passenger, Regional	219		208		605		582
Total passenger revenue	1,249		1,168		3,463		3,233
Segment Reporting Information, Intersegment Revenue	0		0		0		0
Freight and mail	32		32		88		88
Other - net revenue	184		357		511		625
Total Operating Revenues	1,465		1,557		4,062		3,946
Operating expenses
Operating expenses, excluding fuel	755		724		2,230		2,123
Economic fuel	394		363		1,112		1,115
Total Operating Expenses	1,149		1,087		3,342		3,238
Nonoperating income (expense)
Interest income	5		5		15		14
Interest expense	(12)		(13)		(36)		(42)
Other	7		1		34		11
Nonoperating Income (Expense) Total	0		(7)		13		(17)
Income (loss) before income tax	316		463		733		691
Air Group Adjusted [Member]
Operating revenues
Passenger, Mainline	1,030	[1]	960	[1]	2,858	[1]	2,651	[1]
Passenger, Regional	219	[1]	208	[1]	605	[1]	582	[1]
Total passenger revenue	1,249	[1]	1,168	[1]	3,463	[1]	3,233	[1]
Segment Reporting Information, Intersegment Revenue	0	[1]	0	[1]	0	[1]	0	[1]
Freight and mail	32	[1]	32	[1]	88	[1]	88	[1]
Other - net revenue	184	[1]	165	[1]	511	[1]	433	[1]
Total Operating Revenues	1,465	[1]	1,365	[1]	4,062	[1]	3,754	[1]
Operating expenses
Operating expenses, excluding fuel	755	[1]	724	[1]	2,230	[1]	2,123	[1]
Economic fuel	390	[1]	383	[1]	1,129	[1]	1,122	[1]
Total Operating Expenses	1,145	[1]	1,107	[1]	3,359	[1]	3,245	[1]
Nonoperating income (expense)
Interest income	5	[1]	5	[1]	15	[1]	14	[1]
Interest expense	(12)	[1]	(13)	[1]	(36)	[1]	(42)	[1]
Other	7	[1]	1	[1]	34	[1]	11	[1]
Nonoperating Income (Expense) Total	0	[1]	(7)	[1]	13	[1]	(17)	[1]
Income (loss) before income tax	320	[1]	251	[1]	716	[1]	492	[1]
Alaska Mainline [Member]
Operating revenues
Passenger, Mainline	1,030		960		2,858		2,651
Passenger, Regional	0		0		0		0
Total passenger revenue	1,030		960		2,858		2,651
Segment Reporting Information, Intersegment Revenue	0		0		0		0
Freight and mail	30		31		84		85
Other - net revenue	161		145		448		380
Total Operating Revenues	1,221		1,136		3,390		3,116
Operating expenses
Operating expenses, excluding fuel	605		588		1,783		1,704
Economic fuel	338		337		980		987
Total Operating Expenses	943		925		2,763		2,691
Nonoperating income (expense)
Interest income	5		5		15		14
Interest expense	(8)		(9)		(25)		(30)
Other	7		8		34		19
Nonoperating Income (Expense) Total	4		4		24		3
Income (loss) before income tax	282		215		651		428
Alaska Regional [Member]
Operating revenues
Passenger, Mainline	0		0		0		0
Passenger, Regional	219		208		605		582
Total passenger revenue	219		208		605		582
Segment Reporting Information, Intersegment Revenue	0		0		0		0
Freight and mail	2		1		4		3
Other - net revenue	22		19		59		49
Total Operating Revenues	243		228		668		634
Operating expenses
Operating expenses, excluding fuel	162		144		464		440
Economic fuel	52		46		149		135
Total Operating Expenses	214		190		613		575
Nonoperating income (expense)
Interest income	0		0		0		0
Interest expense	0		0		(1)		0
Other	0		(8)		0		(9)
Nonoperating Income (Expense) Total	0		(8)		(1)		(9)
Income (loss) before income tax	29		30		54		50
Horizon [Member]
Operating revenues
Passenger, Mainline	0		0		0		0
Passenger, Regional	0		0		0		0
Total passenger revenue	0		0		0		0
Segment Reporting Information, Intersegment Revenue	99		88		277		274
Freight and mail	0		0		0		0
Other - net revenue	1		1		4		4
Total Operating Revenues	100		89		281		278
Operating expenses
Operating expenses, excluding fuel	85		80		257		253
Economic fuel	0		0		0		0
Total Operating Expenses	85		80		257		253
Nonoperating income (expense)
Interest income	0		0		0		0
Interest expense	(4)		(4)		(10)		(10)
Other	0		1		0		1
Nonoperating Income (Expense) Total	(4)		(3)		(10)		(9)
Income (loss) before income tax	11		6		14		16
Intersegment Elimination [Member]
Operating revenues
Passenger, Mainline	0		0		0		0
Passenger, Regional	0		0		0		0
Total passenger revenue	0		0		0		0
Segment Reporting Information, Intersegment Revenue	(99)		(88)		(277)		(274)
Freight and mail	0		0		0		0
Other - net revenue	0		0		0		0
Total Operating Revenues	(99)		(88)		(277)		(274)
Operating expenses
Operating expenses, excluding fuel	(97)		(88)		(274)		(274)
Economic fuel	0		0		0		0
Total Operating Expenses	(97)		(88)		(274)		(274)
Nonoperating income (expense)
Interest income	0		0		0		0
Interest expense	0		0		0		(2)
Other	0		0		0		0
Nonoperating Income (Expense) Total	0		0		0		(2)
Income (loss) before income tax	(2)		0		(3)		(2)
Special Revenue and Charges [Member]
Operating revenues
Passenger, Mainline	0		0		0		0
Passenger, Regional	0		0		0		0
Total passenger revenue	0		0		0		0
Segment Reporting Information, Intersegment Revenue	0		0		0		0
Freight and mail	0		0		0		0
Other - net revenue	0		192	[2]	0		192	[2]
Total Operating Revenues	0		192		0		192
Operating expenses
Operating expenses, excluding fuel	0		0		0		0
Economic fuel	4	[2]	(20)	[2]	(17)	[2]	(7)	[2]
Total Operating Expenses	4	[2]	(20)	[2]	(17)	[2]	(7)	[2]
Nonoperating income (expense)
Interest income	0		0		0		0
Interest expense	0		0		0		0
Other	0		0		0		0
Nonoperating Income (Expense) Total	0		0		0		0
Income (loss) before income tax	$ (4)	[2]	$ 212	[2]	$ 17	[2]	$ 199	[2]

[1] The adjusted column represents the financial information that is reviewed by management to assess performance of operations and determine capital allocations and does not include certain charges.

[2] Includes mark-to-market fuel-hedge accounting charges and accounting adjustments related to Special mileage plan revenue.