Leases Lessee arrangements - Maturity of lease liabilities (Details) - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018
Operating Leases, Future Minimum Payments Due, Fiscal Year Maturity
Remaining nine months of 2019	$ 158
2020	163
2021	119
2022	76
2023	57
Thereafter	197
Total lease payments	770
Less: Imputed interest	(69)
Total	$ 701
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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Amount of required minimum rental payments for leases having an initial or remaining non-cancelable letter-terms in excess of one year.

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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