OPERATING SEGMENT INFORMATION (DETAILS) (USD $) In Millions, unless otherwise specified	3 Months Ended				6 Months Ended
	Jun. 30, 2013		Jun. 30, 2012		Jun. 30, 2013		Jun. 30, 2012
Operating revenues
Passenger, Mainline	$ 896		$ 863		$ 1,692		$ 1,586
Passenger, Regional	192		188		374		361
Total passenger revenue	1,088		1,051		2,066		1,947
Segment Reporting Information, Intersegment Revenue	0		0		0		0
Freight and mail	30		31		56		55
Other - net	138		132		268		251
Total Operating Revenues	1,256		1,214		2,390		2,253
Operating expenses
Operating expenses, excluding fuel	710		665		1,398		1,313
Economic fuel	372		433		753		751
Total Operating Expenses	1,082		1,098		2,151		2,064
Nonoperating income (expense)
Interest income	4		5		9		10
Interest expense	(14)		(17)		(29)		(34)
Other	5		5		10		11
Nonoperating Income (Expense) Total	(5)		(7)		(10)		(13)
Income (loss) before income tax	169		109		229		176
Air Group Adjusted [Member]
Operating revenues
Passenger, Mainline	896	[1]	863	[1]	1,692	[1]	1,586	[1]
Passenger, Regional	192	[1]	188	[1]	374	[1]	361	[1]
Total passenger revenue	1,088	[1]	1,051	[1]	2,066	[1]	1,947	[1]
Segment Reporting Information, Intersegment Revenue	0		0		0		0
Freight and mail	30	[1]	31	[1]	56	[1]	55	[1]
Other - net	138	[1]	132	[1]	268	[1]	251	[1]
Total Operating Revenues	1,256	[1]	1,214	[1]	2,390	[1]	2,253	[1]
Operating expenses
Operating expenses, excluding fuel	710	[1]	665	[1]	1,398	[1]	1,313	[1]
Economic fuel	371	[1]	363	[1]	740	[1]	701	[1]
Total Operating Expenses	1,081	[1]	1,028	[1]	2,138	[1]	2,014	[1]
Nonoperating income (expense)
Interest income	4	[1]	5	[1]	9	[1]	10	[1]
Interest expense	(14)	[1]	(17)	[1]	(29)	[1]	(34)	[1]
Other	5	[1]	5	[1]	10	[1]	11	[1]
Nonoperating Income (Expense) Total	(5)	[1]	(7)	[1]	(10)	[1]	(13)	[1]
Income (loss) before income tax	170	[1]	179	[1]	242	[1]	226	[1]
Alaska Mainline [Member]
Operating revenues
Passenger, Mainline	896		863		1,692		1,586
Passenger, Regional			0		0		0
Total passenger revenue	896		863		1,692		1,586
Segment Reporting Information, Intersegment Revenue	0		0		0		0
Freight and mail	29		30		54		53
Other - net	120		115		234		218
Total Operating Revenues	1,045		1,008		1,980		1,857
Operating expenses
Operating expenses, excluding fuel	569		532		1,116		1,051
Economic fuel	327		317		650		611
Total Operating Expenses	896		849		1,766		1,662
Nonoperating income (expense)
Interest income	4		4		9		9
Interest expense	(9)		(12)		(21)		(25)
Other	6		5		11		10
Nonoperating Income (Expense) Total	1		(3)		(1)		(6)
Income (loss) before income tax	150		156		213		189
Alaska Regional [Member]
Operating revenues
Passenger, Mainline	0		0		0		0
Passenger, Regional	192		188		374		361
Total passenger revenue	192		188		374		361
Segment Reporting Information, Intersegment Revenue	0		0		0		0
Freight and mail	1		1		2		2
Other - net	16		15		31		29
Total Operating Revenues	209		204		407		392
Operating expenses
Operating expenses, excluding fuel	149		139		296		276
Economic fuel	44		46		90		90
Total Operating Expenses	193		185		386		366
Nonoperating income (expense)
Interest income	0		0		0		0
Interest expense	0		0		0		0
Other	(1)		0		(1)		0
Nonoperating Income (Expense) Total	(1)		0		(1)		0
Income (loss) before income tax	15		19		20		26
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	91		89		186		176
Freight and mail	0		0		0		0
Other - net	2		2		3		4
Total Operating Revenues	93		91		189		180
Operating expenses
Operating expenses, excluding fuel	84		83		173		161
Economic fuel	0		0		0		0
Total Operating Expenses	84		83		173		161
Nonoperating income (expense)
Interest income	0		0		0		0
Interest expense	(4)		(4)		(7)		(8)
Other	1		0		1		1
Nonoperating Income (Expense) Total	(3)		(4)		(6)		(7)
Income (loss) before income tax	6		4		10		12
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	(91)		(89)		(186)		(176)
Freight and mail	0		0		0		0
Other - net	0		0		0		0
Total Operating Revenues	(91)		(89)		(186)		(176)
Operating expenses
Operating expenses, excluding fuel	(92)		(89)		(187)		(175)
Economic fuel	0		0		0		0
Total Operating Expenses	(92)		(89)		(187)		(175)
Nonoperating income (expense)
Interest income	0		1		0		1
Interest expense	(1)		(1)		(1)		0
Other	(1)		0		(1)		0
Nonoperating Income (Expense) Total	(2)		0		(2)		1
Income (loss) before income tax	(1)		0		(1)		0
Special 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
Freight and mail	0		0		0		0
Other - net	0		0		0		0
Total Operating Revenues	0		0		0		0
Operating expenses
Operating expenses, excluding fuel	0		0		0		0
Economic fuel	1	[2]	70	[2]	13	[2]	50	[2]
Total Operating Expenses	1		70		13		50
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	$ (1)		$ (70)		$ (13)		$ (50)

[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] Represents adjustments to reflect the timing of gain or loss recognition resulting from mark-to-market fuel-hedge accounting.