Leases - Components of Lease Expense (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Operating lease expense
Operating lease cost	$ 108	$ 124	$ 214	$ 254
Short-term lease cost	11	12	19	23
Variable lease cost	17	15	39	33
Sublease income	(6)	(17)	(10)	(26)
Total operating costs	130	134	262	284
Finance lease expense
Amortization of right-of-use assets	55	99	116	186
Interest on lease liabilities	4	7	9	16
Total finance lease expense	$ 59	$ 106	$ 125	$ 202

Finance Lease, Cost

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Finance Lease, Cost1 [Abstract]

+ References

No definition available.

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Operating Lease, Cost

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No definition available.

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- Definition

Amount of interest expense on finance lease liability.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
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- Definition

Amount of amortization expense attributable to right-of-use asset from finance lease.

+ References

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- Definition

Amount of lease cost recognized by lessee for lease contract.

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-Publisher FASB
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- Definition

Amount of single lease cost, calculated by allocation of remaining cost of lease over remaining lease term. Includes, but is not limited to, single lease cost, after impairment of right-of-use asset, calculated by amortization of remaining right-of-use asset and accretion of lease liability.

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Amount of short-term lease cost, excluding expense for lease with term of one month or less.

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- Definition

Amount of sublease income excluding finance and operating lease expense.

+ References

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- Definition

Amount of variable lease cost, excluded from lease liability, recognized when obligation for payment is incurred for finance and operating leases.

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