Revenue - Narrative (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Revenue From Contract With Customer [Line Items]
Expiration period for electronic travel certificates	24 months
Operating revenue	$ 7,979	$ 9,589
Advance Ticket Sales
Revenue From Contract With Customer [Line Items]
Revenue recognized	2,600	2,700
Ancillary Fees
Revenue From Contract With Customer [Line Items]
Operating revenue	476	571
Other Operating Revenue
Revenue From Contract With Customer [Line Items]
Operating revenue	650	578
Other Operating Revenue \| Chase and Other Partner Agreements
Revenue From Contract With Customer [Line Items]
Operating revenue	$ 530	$ 473

Electronic Travel Certificates, Expiration Period

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- Definition

[Line Items] for Revenue From Contract With Customer [Table] [Table]

+ References

No definition available.

+ Details

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- 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://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 8
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=118956577&loc=SL49130549-203045

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- Definition

Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=118956577&loc=SL49130543-203045

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=118956577&loc=SL49130545-203045

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