Leases - Maturity of Lease Liabilities (Details) - USD ($) $ in Millions	Sep. 30, 2019	Dec. 31, 2018
Operating Leases
Remainder of 2019	$ 85
2020	352
2021	331
2022	297
2023	264
After 2023	1,098
Total operating lease payments	2,427
Less: Interest	263
Operating Lease, Liability	$ 2,164
Operating Leases Commitments
2019		$ 374
2020		346
2021		308
2022		258
2023		228
Due thereafter		$ 941

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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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due after the fifth 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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