OPERATING SEGMENT INFORMATION (TABLES)

3 Months Ended

Mar. 31, 2012

Segment Reporting [Abstract]

Schedule of Segment Reporting Information, by Segment [Table Text Block]

Operating segment information is as follows (in millions):

	Three Months Ended March 31, 2012
	Alaska
	Mainline			Regional		Horizon			Consolidating			Air Group Adjusted(a)			Special Items			Consolidated
Operating revenues
Passenger
Mainline	$	763.7		$	—	$	—		$	—		$	763.7		$	—		$	763.7
Regional	—			186.7		—			—			186.7			—			186.7
Total passenger revenues	763.7			186.7		—			—			950.4			—			950.4
CPA revenues	—			—		87.0			(87.0		)	—			—			—
Freight and mail	23.5			0.9		—			—			24.4			—			24.4
Other-net	62.5			0.1		1.9			—			64.5			—			64.5
Total operating revenues	849.7			187.7		88.9			(87.0		)	1,039.3			—			1,039.3
Operating expenses
Operating expenses, excluding fuel	519.6			136.8		78.3			(86.6		)	648.1			—			648.1
Economic fuel(c)	294.4			44.3		—			—			338.7			(19.9		)	318.8
Total operating expenses	814.0			181.1		78.3			(86.6		)	986.8			(19.9		)	966.9
Nonoperating income (expense)
Interest income	4.9			—		—			—			4.9			—			4.9
Interest expense	(12.6		)	—		(4.0		)	—			(16.6		)	—			(16.6		)
Other	5.3			—		0.4			0.2			5.9			—			5.9
	(2.4		)	—		(3.6		)	0.2			(5.8		)	—			(5.8		)
Income (loss) before income tax	$	33.3		$	6.6	$	7.0		$	(0.2	)	$	46.7		$	19.9		$	66.6

	Three Months Ended March 31, 2011
	Alaska
	Mainline			Regional		Horizon			Consolidating			Air Group Adjusted(a)			Special Items			Consolidated
Operating revenues
Passenger
Mainline	$	702.4		$	—	$	—		$	—		$	702.4		$	—		$	702.4
Regional	—			176.5		—			—			176.5			—			176.5
Total passenger revenues	702.4			176.5		—			—			878.9			—			878.9
CPA revenues	—			—		94.6			(94.6		)	—			—			—
Freight and mail	23.9			1.0		—			—			24.9			—			24.9
Other-net	59.0			—		2.4			—			61.4			—			61.4
Total operating revenues	785.3			177.5		97.0			(94.6		)	965.2			—			965.2
Operating expenses
Operating expenses, excluding fuel(b)	497.7			132.9		90.2			(94.0		)	626.8			10.1			636.9
Economic fuel(c)	238.4			38.1		—			—			276.5			(82.0		)	194.5
Total operating expenses	736.1			171.0		90.2			(94.0		)	903.3			(71.9		)	831.4
Nonoperating income (expense)
Interest income	8.7			—		—			(1.1		)	7.6			—			7.6
Interest expense	(19.7		)	—		(4.7		)	1.0			(23.4		)	—			(23.4		)
Other	2.1			—		0.8			(0.2		)	2.7			—			2.7
	(8.9		)	—		(3.9		)	(0.3		)	(13.1		)	—			(13.1		)
Income (loss) before income tax	$	40.3		$	6.5	$	2.9		$	(0.9	)	$	48.8		$	71.9		$	120.7

^(a)  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.

^(b)  Refer to Note 12 for a summary of special charges.

^(c)  Represents adjustments to reflect the timing of gain or loss recognition resulting from mark-to-market fuel-hedge accounting.

Total assets were as follows (in millions):

	March 31, 2012			December 31, 2011
Alaska(a)	$	4,894.2		$	4,803.3
Horizon	851.4			846.5
Parent company	1,506.5			1,583.5
Elimination of inter-company accounts	(1,870.1		)	(2,038.3		)
Consolidated	$	5,382.0		$	5,195.0

^(a)  There are no assets associated with purchased capacity flying at Alaska.