Leases - Schedule of Minimum Lease Commitments (Details) - USD ($) $ in Millions	Sep. 30, 2019	Dec. 31, 2018
As of September 30, 2019
2019	$ 46
2020	161
2021	122
2022	98
2023	60
Thereafter	275
Total lease commitments	762
Less: Interest	(109)
Present value of lease liabilities	$ 653
As of December 31, 2018
2019		$ 193
2020		165
2021		123
2022		102
2023		51
Thereafter		32
Total lease commitments		$ 666

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

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