Leases Lessee arrangements - Maturity of lease liabilities (Details) - USD ($) $ in Millions	Sep. 30, 2019	Dec. 31, 2018
Operating Leases, Future Minimum Payments Due, Fiscal Year Maturity
Remaining three months of 2019	$ 47
2020	165
2021	124
2022	77
2023	59
Thereafter	205
Total lease payments	677
Less: Imputed interest	(37)
Total	$ 640
2019		$ 205
2020		154
2021		111
2022		67
2023		50
Thereafter		185
Total		$ 772

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

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Amount of lessee's undiscounted obligation for lease payments for operating lease having an initial or remaining lease term in excess of one year due in remainder of fiscal year following latest fiscal year.

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

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