Additional derivative instruments in hedges at fair value net.

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Impairment of long lived assets to be disposed of net of tax.

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Impairment of long lived assets to be disposed of net of tax per diluted share.

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Number of aircraft engines to be permanently retired from service.

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Number of aircraft temporarily idled.

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Number of aircraft to be permanently retired from service.

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Organization, consolidation and presentation of financial statements.

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The percentage of total aircraft fleet leased under capital or operating leases as of the period-end date

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Amount, before allowance for credit loss, of right to consideration in exchange for good or service transferred to customer, when right is conditioned on something other than passage of time.

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Amount, after allowance for credit loss, of right to consideration in exchange for good or service transferred to customer when right is conditioned on something other than passage of time.

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

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Amount of the cumulative effect on retained earnings before related income tax effect.

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Amount of the cumulative effect on retained earnings net of related income tax effect.

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Aggregate net fair value of all derivative instruments designated as hedging instruments. Includes instruments designated as cash flow hedges, fair value hedges, and hedges of net investments in foreign operations.

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Date the declared dividend will be paid, in CCYY-MM-DD format.

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The per share amount of a dividend declared, but not paid, as of the financial reporting date.

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Date the dividend to be paid was declared, in CCYY-MM-DD format.

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Date the holder must own the stock to be entitled to the dividend, in CCYY-MM-DD format.

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The aggregate amount of write-downs for impairments recognized during the period for long-lived assets held for abandonment, exchange or sale.

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Present value of lessee's discounted obligation for lease payments from operating lease.

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Amount of lessee's right to use underlying asset under operating lease.

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The cash outflow to reacquire common stock during the period.

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Amount of noncash expense for share-based payment arrangement.

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The number of shares authorized to be repurchased by an entity's Board of Directors under a stock repurchase plan.

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The remaining number of shares authorized to be repurchased by an entity's Board of Directors under a stock repurchase plan.

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Total cost of shares repurchased divided by the total number of shares repurchased.

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Number of shares that have been repurchased during the period and are being held in treasury.

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General - Additional Information (Details) $ / shares in Units, € in Millions, $ in Millions		3 Months Ended			9 Months Ended
	Jun. 01, 2019 USD ($)	Feb. 29, 2020 USD ($) $ / shares shares	Nov. 30, 2019 USD ($) air-craft $ / shares	Feb. 28, 2019 USD ($) shares	Feb. 29, 2020 USD ($) $ / shares shares	Feb. 28, 2019 USD ($) shares	Nov. 08, 2019 EUR (€)	Aug. 13, 2019 EUR (€)	May 31, 2019 USD ($)	Jan. 26, 2016 shares
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Gross contract assets related to in-transit packages		$ 491			$ 491				$ 533
Contract assets net of deferred unearned revenue		360			360				364
Contract liabilities related to advance payments from customers		$ 10			$ 10				$ 11
Percentage total aircraft fleet leased		5.00%			5.00%				6.00%
Number of aircraft to be permanently retired from service \| air-craft			10
Number of aircraft engines to be permanently retired from service \| air-craft			12
Noncash impairment charges			$ 66
Noncash impairment charges net of tax			$ 50
Noncash impairment charges net of tax per diluted share \| $ / shares			$ 0.19
Number of aircraft temporarily idled \| air-craft			7
Stock-based compensation		$ 33		$ 33	$ 137	$ 141
Denominated debt as a net investment hedge \| €							€ 392	€ 294
Denominated Additional debt as a net investment hedge \| €							€ 98
Operating lease liability	$ 14,200	14,134			14,134
Operating right-of-use asset	14,100	$ 13,981			$ 13,981
Cumulative effect on retained earnings, before tax	57
Cumulative effect on retained earnings, net of tax	47
Stock repurchase program number of shares authorized to be repurchased \| shares										25,000,000
Number of shares repurchased \| shares		0.0		600,000	20,000.00	6,000,000.0
Treasury stock acquired, average cost per share \| $ / shares					$ 156.90
Payments for repurchase of common stock					$ 3	$ 1,365
Stock repurchase program, remaining number of shares authorized to be repurchased \| shares		5,100,000			5,100,000
Dividends payable, date declared					Feb. 14, 2020
Dividends payable amount per share \| $ / shares		$ 0.65			$ 0.65
Dividends payable, date to be paid					Apr. 01, 2020
Dividends payable, date of record					Mar. 09, 2020
Prepaid Asset [Member]
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Operating right-of-use asset	154
Net Deferred Rent Liability [Member]
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Operating right-of-use asset	$ 309