Leases - Maturities of lease liabilities (Details) - USD ($) $ in Millions	Mar. 31, 2022	Mar. 31, 2021	Apr. 01, 2019
Operating Leases
2023	$ 328
2024	310
2025	268
2026	223
2027	180
Thereafter	506
Total lease payments	1,815
Less imputed interest	(152)
Present value of lease liabilities	1,663	$ 2,257	$ 2,200
Finance Leases
2023	29
2024	29
2025	27
2026	25
2027	24
Thereafter	103
Total lease payments	237
Less imputed interest	(27)
Present value of lease liabilities	210	$ 228
Total
2023	357
2024	339
2025	295
2026	248
2027	204
Thereafter	609
Total lease payments	2,052
Less imputed interest	(179)
Present value of lease liabilities	1,873
Minimum sublease income	$ 201

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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=123408670&loc=SL77918701-209980

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 45
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=123391704&loc=SL77918627-209977

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Amount of lessee's undiscounted obligation for lease payment for finance lease to be paid in fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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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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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 45
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=123391704&loc=SL77918627-209977

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