Term of lessee's operating lease renewal, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Term of lessee's operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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- Definition

Amount of minimum lease payments for sale-leaseback transactions accounted for using the deposit method or as a financing.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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-Section 50
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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

Contractually required future rental payments receivable on noncancelable subleasing arrangements.

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- Definition

Rental expense for the reporting period incurred under operating leases, including minimum and any contingent rent expense, net of related sublease income.

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Lease Obligations - Narrative (Details) - USD ($) $ in Millions	12 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Mar. 31, 2017
Operating Leased Assets [Line Items]
Future minimum lease payments for sale leaseback transaction	$ 49
Minimum sublease income, due under future noncancelable subleases	133
Rent expense	$ 576	$ 568	$ 474
Renewal option increments for leases (in years)	5 years
Building \| Minimum
Operating Leased Assets [Line Items]
Lease term	1 year
Building \| Maximum
Operating Leased Assets [Line Items]
Lease term	15 years
Equipment \| Minimum
Operating Leased Assets [Line Items]
Lease term	1 year
Equipment \| Maximum
Operating Leased Assets [Line Items]
Lease term	6 years