Leases - Maturities of lease liabilities (Details) $ in Millions	Mar. 31, 2020 USD ($)
Operating Leases
2021	$ 398
2022	371
2023	310
2024	252
2025	213
Thereafter	730
Total lease payments	2,274
Less imputed interest	(260)
Present value of lease liabilities	2,014
Finance Leases
2021	19
2022	19
2023	18
2024	17
2025	16
Thereafter	110
Total lease payments	199
Less imputed interest	(33)
Present value of lease liabilities	166
Total
2021	417
2022	390
2023	328
2024	269
2025	229
Thereafter	840
Total lease payments	2,473
Less imputed interest	(293)
Present value of lease liabilities	$ 2,180

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
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-URI http://asc.fasb.org/extlink&oid=77888426&loc=SL77918701-209980

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