Net costs for terminal construction project subject to underlying ground lease.

No definition available.

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- Definition

Amount of gain (loss) on sale of investment in debt security measured at amortized cost (held-to-maturity), including other-than-temporary impairment (OTTI).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition

Amount before accumulated depreciation of additions or improvements to assets held under a lease arrangement.

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- Definition

Amount of cumulative effect of the change in accounting principle or new accounting pronouncement on retained earnings or other components of equity or net assets in the statement of financial position as of the beginning of the earliest period presented.

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- References

No definition available.

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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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- Definition

Stated as a percentage, the estimated or actual value of the asset at the end of its useful life or when it is no longer serviceable (cannot be used for its original purpose) divided by its [historical] capitalized cost.

+ References

No definition available.

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- Definition

Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

+ References

No definition available.

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Summary of Significant Accounting Policies (Details 1) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Jan. 01, 2017
Property, Plant and Equipment [Line Items]
Debt Securities, Held-to-maturity, Sold, Realized Gain (Loss)	$ 0	$ 0	$ 0
New Accounting Pronouncement or Change in Accounting Principle, Cumulative Effect of Change on Equity or Net Assets				$ 58
JFK Terminal 5 [Member]
Property, Plant and Equipment [Line Items]
Leasehold Improvements, Gross		76
Net Costs For Terminal Construction Project Subject To Underlying Ground Lease		$ 637
Aircraft [Member]
Property and Equipment
Estimated Useful Life	25 years
Residual Value	20.00%
In-flight entertainment systems [Member]
Property and Equipment
Residual Value	0.00%
Aircraft Parts [Member]
Property and Equipment
Residual Value	10.00%
Flight equipment leasehold improvements [Member]
Property and Equipment
Residual Value	0.00%
Ground property and equipment [Member]
Property and Equipment
Residual Value	0.00%
Leasehold improvements-other [Member]
Property and Equipment
Residual Value	0.00%
Buildings on Leased Land Member
Property and Equipment
Residual Value	0.00%
JFK Terminal 5 International [Member]
Property, Plant and Equipment [Line Items]
Net Costs For Terminal Construction Project Subject To Underlying Ground Lease	$ 207
Minimum [Member] \| In-flight entertainment systems [Member]
Property and Equipment
Estimated Useful Life	5 years
Minimum [Member] \| Ground property and equipment [Member]
Property and Equipment
Estimated Useful Life	2 years
Maximum [Member] \| In-flight entertainment systems [Member]
Property and Equipment
Estimated Useful Life	10 years
Maximum [Member] \| Ground property and equipment [Member]
Property and Equipment
Estimated Useful Life	10 years