OPERATING SEGMENT INFORMATION (DETAILS) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2014		Dec. 31, 2013		Dec. 31, 2012
Operating revenues
Passenger, Mainline	$ 3,774		$ 3,490		$ 3,284
Passenger, Regional	805		777		746
Total passenger revenue	4,579		4,267		4,030
CPA revenues	0		0		0
Freight and mail	114		113		111
Other Net and Special Revenue	675		776		516
Total Operating Revenues	5,368		5,156		4,657
Operating expenses
Operating expenses, excluding fuel	2,988		2,851		2,666
Economic fuel	1,418		1,467		1,459
Total Operating Expenses	4,406		4,318		4,125
Nonoperating income (expense)
Interest income	21		18		19
Interest expense	(48)		(56)		(64)
Other	40		16		27
Nonoperating Income (Expense) Total	13		(22)		(18)
Income (loss) before income tax	975		816		514
Income before income tax	975		816		514
Depreciation	294		270		264
Capital expenditures	694		566		518
Total assets	6,181		5,838
Air Group Adjusted [Member]
Operating revenues
Passenger, Mainline	3,774	[1]	3,490	[1]	3,284	[1]
Passenger, Regional	805	[1]	777	[1]	746	[1]
Total passenger revenue	4,579	[1]	4,267	[1]	4,030	[1]
CPA revenues	0		0		0
Freight and mail	114	[1]	113	[1]	111	[1]
Other Net and Special Revenue	675	[1]	584	[1]	516	[1]
Total Operating Revenues	5,368	[1]	4,964	[1]	4,657	[1]
Operating expenses
Operating expenses, excluding fuel	3,018	[1]	2,851	[1]	2,666	[1]
Economic fuel	1,441	[1]	1,475	[1]	1,421	[1]
Total Operating Expenses	4,459	[1]	4,326	[1]	4,087	[1]
Nonoperating income (expense)
Interest income	21	[1]	18	[1]	19	[1]
Interest expense	(48)	[1]	(56)	[1]	(64)	[1]
Other	40	[1]	16	[1]	27	[1]
Nonoperating Income (Expense) Total	13	[1]	(22)	[1]	(18)	[1]
Income (loss) before income tax	922	[1]	616	[1]	552	[1]
Alaska Airlines [Member]
Nonoperating income (expense)
Depreciation	243	[2]	223	[2]	217	[2]
Capital expenditures	659	[2]	494	[2]	477	[2]
Total assets	6,772	[2]	5,832	[2]
Alaska Mainline [Member]
Operating revenues
Passenger, Mainline	3,774		3,490		3,284
Passenger, Regional	0		0		0
Total passenger revenue	3,774		3,490		3,284
CPA revenues	0		0		0
Freight and mail	109		109		107
Other Net and Special Revenue	592		513		448
Total Operating Revenues	4,475		4,112		3,839
Operating expenses
Operating expenses, excluding fuel	2,417		2,293		2,131
Economic fuel	1,251		1,294		1,238
Total Operating Expenses	3,668		3,587		3,369
Nonoperating income (expense)
Interest income	20		18		19
Interest expense	(32)		(38)		(47)
Other	39		25		24
Nonoperating Income (Expense) Total	27		5		(4)
Income (loss) before income tax	834		530		466
Alaska Regional [Member]
Operating revenues
Passenger, Mainline	0		0		0
Passenger, Regional	805		777		746
Total passenger revenue	805		777		746
CPA revenues	0		0		0
Freight and mail	5		4		4
Other Net and Special Revenue	78		66		61
Total Operating Revenues	888		847		811
Operating expenses
Operating expenses, excluding fuel	623		585		566
Economic fuel	190		181		183
Total Operating Expenses	813		766		749
Nonoperating income (expense)
Interest income	0		0		0
Interest expense	0		0		0
Other	(1)		(12)		0
Nonoperating Income (Expense) Total	(1)		(12)		0
Income (loss) before income tax	74		69		62
Horizon [Member]
Operating revenues
Passenger, Mainline	0		0		0
Passenger, Regional	0		0		0
Total passenger revenue	0		0		0
CPA revenues	371		368		369
Freight and mail	0		0		0
Other Net and Special Revenue	5		5		7
Total Operating Revenues	376		373		376
Operating expenses
Operating expenses, excluding fuel	349		341		338
Economic fuel	0		0		0
Total Operating Expenses	349		341		338
Nonoperating income (expense)
Interest income	0		0		0
Interest expense	(12)		(14)		(16)
Other	2		2		2
Nonoperating Income (Expense) Total	(10)		(12)		(14)
Income (loss) before income tax	17		20		24
Depreciation	51		47		47
Capital expenditures	35		72		41
Total assets	818		840
Parent [Member]
Nonoperating income (expense)
Depreciation	0		0		0
Total assets	3,552		2,762
Intersegment Eliminations
Operating revenues
Passenger, Mainline	0		0		0
Passenger, Regional	0		0		0
Total passenger revenue	0		0		0
CPA revenues	(371)		(368)		(369)
Freight and mail					0
Other Net and Special Revenue					0
Total Operating Revenues	(371)		(368)		(369)
Operating expenses
Operating expenses, excluding fuel	(371)		(368)		(369)
Economic fuel	0		0		0
Total Operating Expenses	(371)		(368)		(369)
Nonoperating income (expense)
Interest income	1		0		0
Interest expense	(4)		(4)		(1)
Other	0		1		1
Nonoperating Income (Expense) Total	(3)		(3)		0
Income (loss) before income tax	(3)		(3)		0
Total assets	(4,961)		(3,596)
Special Charges [Member]
Operating revenues
Passenger, Mainline	0		0		0
Passenger, Regional	0		0		0
Total passenger revenue	0		0		0
CPA revenues	0		0		0
Freight and mail	0		0		0
Other Net and Special Revenue		[3]	192		0
Total Operating Revenues	0	[3]	192		0
Operating expenses
Operating expenses, excluding fuel	(30)		0		0	[3]
Economic fuel	(23)	[3]	(8)	[3]	38	[3]
Total Operating Expenses	(53)	[3]	(8)	[3]	38	[3]
Nonoperating income (expense)
Interest income	0		0		0
Interest expense	0		0		0
Other	0		0		0
Nonoperating Income (Expense) Total	0		0		0
Income (loss) before income tax	$ 53	[3]	$ 200	[3]	$ (38)	[3]

[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 income and charges.

[2] There are no depreciation expenses, capital expenditures or assets associated with purchased capacity flying at Alaska Regional.

[3] Includes accounting adjustments related to Special mileage plan revenue, mark-to-market fuel-hedge accounting charges, non-cash curtailment gain, and a one-time gain related to a legal matter.