Leases - Components of Lease Costs (Details) $ in Millions	12 Months Ended
Dec. 31, 2019 USD ($)
Components of lease cost
Finance lease cost	$ 30
Operating lease cost	1,645
Short-term lease cost	38
Variable lease cost	534
Sublease income	(24)
Total lease cost	2,223
Gains on sale and leaseback transactions, net	$ 41

Amount of finance lease cost recognized by lessee for lease contract.

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- Definition

Amount of lease cost recognized by lessee for lease contract.

+ References

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- References

No definition available.

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- Definition

Amount of single lease cost, calculated by allocation of remaining cost of lease over remaining lease term. Includes, but is not limited to, single lease cost, after impairment of right-of-use asset, calculated by amortization of remaining right-of-use asset and accretion of lease liability.

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- Definition

Amount of gain (loss) on sale and leaseback transaction from transfer of asset accounted for as sale.

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Amount of short-term lease cost, excluding expense for lease with term of one month or less.

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Amount of sublease income excluding finance and operating lease expense.

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- Definition

Amount of variable lease cost, excluded from lease liability, recognized when obligation for payment is incurred for finance and operating leases.

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