OPERATING SEGMENT INFORMATION (DETAILS) (USD $) In Millions, unless otherwise specified	3 Months Ended				9 Months Ended
	Sep. 30, 2013		Sep. 30, 2012		Sep. 30, 2013		Sep. 30, 2012
Operating revenues
Passenger, Mainline	$ 960		$ 905		$ 2,651		$ 2,491
Passenger, Regional	208		198		582		559
Total passenger revenue	1,168		1,103		3,233		3,050
Segment Reporting Information, Intersegment Revenue	0		0		0		0
Freight and mail	32		30		88		85
Other Net and Special Revenue	357		139		625		390
Total Operating Revenues	1,557		1,272		3,946		3,525
Operating expenses
Operating expenses, excluding fuel	724		666		2,123		1,980
Economic fuel	363		337		1,115		1,087
Total Operating Expenses	1,087		1,003		3,238		3,067
Nonoperating income (expense)
Interest income	5		5		14		15
Interest expense	(13)		(15)		(42)		(49)
Other	1		6		11		18
Nonoperating Income (Expense) Total	(7)		(4)		(17)		(16)
Income (loss) before income tax	463		265		691		442
Air Group Adjusted [Member]
Operating revenues
Passenger, Mainline	960	[1]	905	[1]	2,651	[1]	2,491	[1]
Passenger, Regional	208	[1]	198	[1]	582	[1]	559	[1]
Total passenger revenue	1,168	[1]	1,103	[1]	3,233	[1]	3,050	[1]
Segment Reporting Information, Intersegment Revenue	0		0		0		0
Freight and mail	32	[1]	30	[1]	88	[1]	85	[1]
Other Net and Special Revenue	165	[1]	139	[1]	433	[1]	390	[1]
Total Operating Revenues	1,365	[1]	1,272	[1]	3,754	[1]	3,525	[1]
Operating expenses
Operating expenses, excluding fuel	724	[1]	666	[1]	2,123	[1]	1,980	[1]
Economic fuel	383	[1]	358	[1]	1,122	[1]	1,058	[1]
Total Operating Expenses	1,107	[1]	1,024	[1]	3,245	[1]	3,038	[1]
Nonoperating income (expense)
Interest income	5	[1]	5	[1]	14	[1]	15	[1]
Interest expense	(13)	[1]	(15)	[1]	(42)	[1]	(49)	[1]
Other	1	[1]	6	[1]	11	[1]	18	[1]
Nonoperating Income (Expense) Total	(7)	[1]	(4)	[1]	(17)	[1]	(16)	[1]
Income (loss) before income tax	251	[1]	244	[1]	492	[1]	471	[1]
Alaska Mainline [Member]
Operating revenues
Passenger, Mainline	960		905		2,651		2,491
Passenger, Regional			0		0		0
Total passenger revenue	960		905		2,651		2,491
Segment Reporting Information, Intersegment Revenue	0		0		0		0
Freight and mail	31		28		85		82
Other Net and Special Revenue	145		121		380		339
Total Operating Revenues	1,136		1,054		3,116		2,912
Operating expenses
Operating expenses, excluding fuel	588		532		1,704		1,583
Economic fuel	337		312		987		923
Total Operating Expenses	925		844		2,691		2,506
Nonoperating income (expense)
Interest income	5		5		14		15
Interest expense	(9)		(11)		(30)		(37)
Other	8		6		19		17
Nonoperating Income (Expense) Total	4		0		3		(5)
Income (loss) before income tax	215		210		428		401
Alaska Regional [Member]
Operating revenues
Passenger, Mainline	0		0		0		0
Passenger, Regional	208		198		582		559
Total passenger revenue	208		198		582		559
Segment Reporting Information, Intersegment Revenue	0		0		0		0
Freight and mail	1		2		3		3
Other Net and Special Revenue	19		16		49		45
Total Operating Revenues	228		216		634		607
Operating expenses
Operating expenses, excluding fuel	144		145		440		421
Economic fuel	46		46		135		135
Total Operating Expenses	190		191		575		556
Nonoperating income (expense)
Interest income	0		0		0		0
Interest expense	0		0		0		0
Other	(8)		0		(9)		0
Nonoperating Income (Expense) Total	(8)		0		(9)		0
Income (loss) before income tax	30		25		50		51
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	88		96		274		272
Freight and mail	0		0		0		0
Other Net and Special Revenue	1		2		4		6
Total Operating Revenues	89		98		278		278
Operating expenses
Operating expenses, excluding fuel	80		86		253		248
Economic fuel	0		0		0		0
Total Operating Expenses	80		86		253		248
Nonoperating income (expense)
Interest income	0		0		0		0
Interest expense	(4)		(4)		(10)		(12)
Other	1		0		1		1
Nonoperating Income (Expense) Total	(3)		(4)		(9)		(11)
Income (loss) before income tax	6		8		16		19
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	(88)		(96)		(274)		(272)
Freight and mail	0		0		0		0
Other Net and Special Revenue	0		0		0		0
Total Operating Revenues	(88)		(96)		(274)		(272)
Operating expenses
Operating expenses, excluding fuel	(88)		(97)		(274)		(272)
Economic fuel	0		0		0		0
Total Operating Expenses	(88)		(97)		(274)		(272)
Nonoperating income (expense)
Interest income	0		0		0		0
Interest expense	0		0		(2)		0
Other	0		0		0		0
Nonoperating Income (Expense) Total	0		0		(2)		0
Income (loss) before income tax	0		1		(2)		0
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 and Special Revenue	192	[2]	0		192	[2]	0
Total Operating Revenues	192		0		192		0
Operating expenses
Operating expenses, excluding fuel	0		0		0		0
Economic fuel	(20)	[2]	(21)	[2]	(7)	[2]	29	[2]
Total Operating Expenses	(20)		(21)		(7)		29
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	$ 212		$ 21		$ 199		$ (29)

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