OPERATING SEGMENT INFORMATION (DETAILS) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2013		Mar. 31, 2012
Operating revenues
Passenger, Mainline	$ 796		$ 723
Passenger, Regional	182		173
Total passenger revenue	978		896
Segment Reporting Information, Intersegment Revenue	0		0
Freight and mail	26		24
Other - net	129		119
Total Operating Revenues	1,133		1,039
Operating expenses
Operating expenses, excluding fuel	688		648
Economic fuel	381		319
Total Operating Expenses	1,069		967
Nonoperating income (expense)
Interest income	4		5
Interest expense	(16)		(17)
Other	7		6
Nonoperating Income (Expense) Total	(5)		(6)
Income (loss) before income tax	59		66
Air Group Adjusted [Member]
Operating revenues
Passenger, Mainline	796	[1]	723	[1]
Passenger, Regional	182	[1]	173	[1]
Total passenger revenue	978	[1]	896	[1]
Segment Reporting Information, Intersegment Revenue	0		0
Freight and mail	26	[1]	24	[1]
Other - net	129	[1]	119	[1]
Total Operating Revenues	1,133	[1]	1,039	[1]
Operating expenses
Operating expenses, excluding fuel	688	[1]	648	[1]
Economic fuel	369	[1]	339	[1]
Total Operating Expenses	1,057	[1]	987	[1]
Nonoperating income (expense)
Interest income	4	[1]	5	[1]
Interest expense	(16)	[1]	(17)	[1]
Other	7	[1]	6	[1]
Nonoperating Income (Expense) Total	(5)	[1]	(6)	[1]
Income (loss) before income tax	71	[1]	46	[1]
Alaska Mainline [Member]
Operating revenues
Passenger, Mainline	796		723
Passenger, Regional	0		0
Total passenger revenue	796		723
Segment Reporting Information, Intersegment Revenue	0		0
Freight and mail	25		23
Other - net	113		103
Total Operating Revenues	934		849
Operating expenses
Operating expenses, excluding fuel	547		520
Economic fuel	323		294
Total Operating Expenses	870		814
Nonoperating income (expense)
Interest income	4		5
Interest expense	(11)		(13)
Other	6		6
Nonoperating Income (Expense) Total	(1)		(2)
Income (loss) before income tax	63		33
Alaska Regional [Member]
Operating revenues
Passenger, Mainline	0		0
Passenger, Regional	182		173
Total passenger revenue	182		173
Segment Reporting Information, Intersegment Revenue	0		0
Freight and mail	1		1
Other - net	14		14
Total Operating Revenues	197		188
Operating expenses
Operating expenses, excluding fuel	147		137
Economic fuel	46		45
Total Operating Expenses	193		182
Nonoperating income (expense)
Interest income	0		0
Interest expense	0		0
Other	0		0
Nonoperating Income (Expense) Total	0		0
Income (loss) before income tax	4		6
Horizon [Member]
Operating revenues
Passenger, Mainline	0		0
Passenger, Regional	0		0
Total passenger revenue	0		0
Segment Reporting Information, Intersegment Revenue	94		87
Freight and mail	0		0
Other - net	2		2
Total Operating Revenues	96		89
Operating expenses
Operating expenses, excluding fuel	89		78
Economic fuel	0		0
Total Operating Expenses	89		78
Nonoperating income (expense)
Interest income	0		0
Interest expense	(3)		(4)
Other	0		0
Nonoperating Income (Expense) Total	(3)		(4)
Income (loss) before income tax	4		7
Intersegment Elimination [Member]
Operating revenues
Passenger, Mainline	0		0
Passenger, Regional	0		0
Total passenger revenue	0		0
Segment Reporting Information, Intersegment Revenue	(94)		(87)
Freight and mail	0		0
Other - net	0		0
Total Operating Revenues	(94)		(87)
Operating expenses
Operating expenses, excluding fuel	(95)		(87)
Economic fuel	0		0
Total Operating Expenses	(95)		(87)
Nonoperating income (expense)
Interest income	0		0
Interest expense	(2)		0
Other	1		0
Nonoperating Income (Expense) Total	(1)		0
Income (loss) before income tax	0		0
Special Charges [Member]
Operating revenues
Passenger, Mainline	0		0
Passenger, Regional	0		0
Total passenger revenue	0		0
Segment Reporting Information, Intersegment Revenue	0		0
Freight and mail	0		0
Other - net	0		0
Total Operating Revenues	0		0
Operating expenses
Operating expenses, excluding fuel	0		0	[2]
Economic fuel	12		(20)
Total Operating Expenses	12		(20)
Nonoperating income (expense)
Interest income	0		0
Interest expense	0		0
Other	0		0
Nonoperating Income (Expense) Total	0		0
Income (loss) before income tax	$ (12)		$ 20

[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.