COVER - shares	9 Months Ended
	Sep. 30, 2019	Oct. 31, 2019
Cover page.
Document Type	10-Q
Document Transition Report	false
Document Period End Date	Sep. 30, 2019
Document Quarterly Report	true
Entity File Number	1-8957
Entity Registrant Name	ALASKA AIR GROUP, INC.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	91-1292054
Title of 12(b) Security	Common stock, $0.01 par value
Security Exchange Name	NYSE
Trading Symbol	ALK
Entity Address, Address Line One	19300 International Boulevard,
Entity Address, City or Town	Seattle,
Entity Address, State or Province	WA
Entity Address, Postal Zip Code	98188
City Area Code	(206)
Local Phone Number	392-5040
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		123,173,426
Amendment Flag	false
Document Fiscal Year Focus	2019
Document Fiscal Period Focus	Q3
Entity Central Index Key	0000766421
Current Fiscal Year End Date	--12-31