Leases (Details 4) $ in Millions	May. 31, 2015 USD ($)
Schedule of Future Minimum Operating Lease Payments [Line Items]
2016	$ 1,137
2017	1,246
2018	860
2019	730
2020	584
Thereafter	3,625
Total	8,182
Aircraft and Related Equipment [Member]
Schedule of Future Minimum Operating Lease Payments [Line Items]
2016	461
2017	400
2018	329
2019	273
2020	190
Thereafter	360
Total	2,013
Facilities and Other [Member]
Schedule of Future Minimum Operating Lease Payments [Line Items]
2016	676
2017	846
2018	531
2019	457
2020	394
Thereafter	3,265
Total	$ 6,169

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Amount of required minimum rental payments for leases having an initial or remaining non-cancelable letter-terms in excess of one year.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

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-SubTopic 10

-Section 55

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

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-Name Accounting Standards Codification

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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