Contract With Customer, Liability, Cancellation Refunds

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- Definition

Loyalty And Other Incentive Programs, Expiration Period For Reward Points

+ References

No definition available.

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- Definition

Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable, classified as current.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=118944033&loc=SL49130531-203044

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=118944033&loc=SL49130532-203044

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 8
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=118956577&loc=SL49130549-203045

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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 after tax of increase (decrease) to equity or (increase) decrease to net assets, resulting from the cumulative effect adjustment of a new accounting principle applied in the period of adoption.

+ References

No definition available.

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- Definition

Amount of increase (decrease) in obligation to transfer good or service to customer for which consideration has been received or is receivable.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3602-108585

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- Definition

Cash receipts from customers during the current period which are usually for sales of goods and services.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 25
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3536-108585

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Details

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REVENUE RECOGNITION Deferred Revenue Arrangements (Details) - USD ($) $ in Millions	3 Months Ended		12 Months Ended
	Sep. 30, 2019	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Jan. 01, 2018	Jan. 01, 2017
Revenue Recognition, Multiple-deliverable Arrangements [Line Items]
Revenues recognized from the beginning balance			$ (134)	$ (109)
Cancellations			(15)	(10)
One-time adjustment to retained earnings at adoption of ASC 606					$ 189	$ 280
Payments received from travelers net of amounts estimated to be payable to travel service providers and other			220	149
Deferred revenue in deferred merchant bookings \| Deferred Merchant Bookings
Revenue Recognition, Multiple-deliverable Arrangements [Line Items]
Contract liability, beginning of year		$ 151	149	151
Contract liability, end of year			220	149
Customer Incentive Programs
Revenue Recognition, Multiple-deliverable Arrangements [Line Items]
Increase (Decrease) in Contract with Customer, Liability	$ (37)
Loyalty Programs \| Customer Incentive Programs
Revenue Recognition, Multiple-deliverable Arrangements [Line Items]
Reward expiration period		3 years
Increase (Decrease) in Contract with Customer, Liability		$ (27)
Loyalty Programs \| Customer Incentive Programs \| Accrued Liabilities
Revenue Recognition, Multiple-deliverable Arrangements [Line Items]
Contract liability, beginning of year			73
Contract liability, end of year			80	73
Other customer incentive programs \| Customer Incentive Programs \| Accrued Liabilities
Revenue Recognition, Multiple-deliverable Arrangements [Line Items]
Contract liability, beginning of year			61
Contract liability, end of year			22	$ 61
Accounting Standards Update 2014-09
Revenue Recognition, Multiple-deliverable Arrangements [Line Items]
One-time adjustment to retained earnings at adoption of ASC 606					189
Retained Earnings
Revenue Recognition, Multiple-deliverable Arrangements [Line Items]
One-time adjustment to retained earnings at adoption of ASC 606					430	$ 271
Retained Earnings \| Accounting Standards Update 2014-09
Revenue Recognition, Multiple-deliverable Arrangements [Line Items]
One-time adjustment to retained earnings at adoption of ASC 606			$ 0		$ (32)