Leases - Operating Lease Income and Related Depreciation Expense (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Leases [Abstract]
Operating lease income	$ 1,316
Operating lease income		$ 1,047
Lessee, Lease, Description [Line Items]
Depreciation expense		$ 811
Assets subject to operating leases
Lessee, Lease, Description [Line Items]
Depreciation expense	$ 997

The amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives. Includes production and non-production related depreciation.

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- References

No definition available.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Amount of operating lease income from lease payments and variable lease payments paid and payable to lessor. Includes, but is not limited to, variable lease payments not included in measurement of lease receivable.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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- Definition

The total depreciation charge recorded for property subject to or held for lease.

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- Definition

The total amount of revenue recognized for the period from operating leases, including minimum lease revenue, contingent revenue, percentage revenue and sublease revenue.

+ References

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