Leases - Cash Flow From Lease Transactions (Details) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2019 USD ($)	Jun. 30, 2019 USD ($)
Leases
Gains and losses on sale and leaseback transactions, net	$ 5	$ 41
Cash paid for amounts included in the measurement of lease liabilities
Operating cash outflows from finance leases		4
Financing cash outflows from finance leases		2
Operating cash outflows from operating leases		762
ROU assets obtained in exchange for new finance lease liabilities	77	77
ROU assets obtained in exchange for new operating lease liabilities	$ 5,771	5,771
ROU assets obtained in exchange for new finance lease liabilities - post adoption
ROU assets obtained in exchange for new operating lease liabilities - post adoption		$ 927

No definition available.

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- Definition

Gross amount of lessee's right to use underlying asset under finance lease.

+ References

No definition available.

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Gross amount of lessee's right to use underlying asset under operating lease.

+ References

No definition available.

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- Definition

Amount of interest paid on finance lease liability.

+ References

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- Definition

Amount of cash outflow for principal payment on finance lease.

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- Definition

Amount of cash outflow from operating lease, excluding payments to bring another asset to condition and location necessary for its intended use.

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- Definition

Amount of increase in right-of-use asset obtained in exchange for finance lease liability.

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- Definition

Amount of increase in right-of-use asset obtained in exchange for operating 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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