XML 42 R30.htm IDEA: XBRL DOCUMENT
v3.19.2

REVENUE FROM CONTRACTS WITH CUSTOMERS - Contract Liabilities Activity (Details) - Mileage Plan Revenue [Member] - USD ($) $ in Millions | 6 Months Ended
--- | ---
Jun. 30, 2019 | Jun. 30, 2018
Change in Contract with Customer, Liability [Roll Forward] |  |
Total Deferred Revenue balance at January 1 | $ 1,874 | $ 1,725
Increase in liability for mileage credits issued | 451 | 402
Total Deferred Revenue balance at June 30 | 1,949 | 1,777
Passenger revenue [Member] |  |
Change in Contract with Customer, Liability [Roll Forward] |  |
Revenue recognized | (325) | (306)
Mileage plan other revenue [Member] |  |
Change in Contract with Customer, Liability [Roll Forward] |  |
Revenue recognized | $ (51) | $ (44)

X
- Definition Change in Contract with Customer, Liability [Roll Forward] + References No definition available. + Details
Name: | alk_ChangeinContractwithCustomerLiabilityRollForward
Namespace Prefix: | alk_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Contract with Customer, Liability, Increase From Issuance of Credits + References No definition available. + Details
Name: | alk_ContractwithCustomerLiabilityIncreaseFromIssuanceofCredits
Namespace Prefix: | alk_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=82913815&loc=SL49130531-203044 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=82913815&loc=SL49130532-203044 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 50 -Paragraph 8 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=109196051&loc=SL49130549-203045 + Details
Name: | us-gaap_ContractWithCustomerLiability
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Amount of revenue recognized that was previously included in balance of obligation to transfer good or service to customer for which consideration from customer has been received or is due. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 50 -Paragraph 8 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=109196051&loc=SL49130549-203045 + Details
Name: | us-gaap_ContractWithCustomerLiabilityRevenueRecognized
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Details
Name: | us-gaap_ContractWithCustomerSalesChannelAxis=alk_MileagePlanRevenueMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_ProductOrServiceAxis=alk_PassengerServicesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_ProductOrServiceAxis=alk_MileagePlanServicesOtherMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |