Leases - Maturities of lease liabilities (Details) - USD ($) $ in Millions	Mar. 31, 2021	Mar. 31, 2020	Apr. 01, 2019
Operating Leases
2022	$ 433
2023	401
2024	332
2025	283
2026	233
Thereafter	823
Total lease payments	2,505
Less imputed interest	(248)
Present value of lease liabilities	2,257	$ 2,014	$ 2,200
Finance Leases
2022	28
2023	28
2024	27
2025	25
2026	24
Thereafter	130
Total lease payments	262
Less imputed interest	(34)
Present value of lease liabilities	228	$ 166
Total
2022	461
2023	429
2024	359
2025	308
2026	257
Thereafter	953
Total lease payments	2,767
Less imputed interest	(282)
Present value of lease liabilities	$ 2,485

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Lease, Liability

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=121609121&loc=SL77918701-209980

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-Publisher FASB
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-Topic 842
-SubTopic 20
-Section 45
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121603541&loc=SL77918627-209977

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Amount of lessee's undiscounted obligation for lease payments for finance lease.

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Amount of lessee's undiscounted obligation for lease payment for operating lease.

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

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 20
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-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121603541&loc=SL77918627-209977

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