COVID-19 PANDEMIC (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020
Risks and Uncertainties [Abstract]
Restructuring Charges	$ 11	$ 0	$ 220
Restructuring Reserve	91		127
Payments for Restructuring	(47)
Leased Aircraft Return Costs	$ 18		$ 209

Leased Aircraft Return Costs

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- Definition

Amount of cash payments made as the result of exit or disposal activities. Excludes payments associated with a discontinued operation or an asset retirement obligation.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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-Publisher FASB
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Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation.

+ References

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- Definition

Carrying amount (including both current and noncurrent portions of the accrual) as of the balance sheet date pertaining to a specified type of cost associated with exit from or disposal of business activities or restructuring pursuant to a duly authorized plan.

+ References

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- References

No definition available.

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