OPERATING SEGMENT INFORMATION, ASSETS (Details) (USD $) In Millions, unless otherwise specified	Jun. 30, 2013		Dec. 31, 2012
Total assets	$ 5,852		$ 5,505
Alaska Airlines [Member]
Total assets	5,582	[1]	5,177	[1]
Horizon [Member]
Total assets	868		823
Parent [Member]
Total assets	2,070		1,832
Intersegment Elimination [Member]
Total assets	$ (2,668)		$ (2,327)

[1] There are no assets associated with purchased capacity flying at Alaska.