Leases - Components of Lease Costs (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Components of lease cost
Finance lease cost	$ 52	$ 35	$ 14
Operating lease cost	1,126	1,181	1,257
Short-term lease cost	21	28	24
Variable lease cost	336	343	364
Sublease income	(46)	(28)	(22)
Total lease cost	1,489	1,558	1,637
Gains on sale and leaseback transactions, net	$ 7	$ 0	$ 36

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

No definition available.

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- Definition

Amount of lease cost recognized by lessee for lease contract.

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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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