Lease Income under Operating Leases (Property Available for Lease) (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Land [Member]
Operating Leased Assets [Line Items]
Property Subject to or Available for Operating Lease, Gross	$ 410	$ 414
Building and Building Improvements [Member]
Operating Leased Assets [Line Items]
Property Subject to or Available for Operating Lease, Gross	481	506
Equipment [Member]
Operating Leased Assets [Line Items]
Property Subject to or Available for Operating Lease, Gross	368	306
Property And Equipment [Member]
Operating Leased Assets [Line Items]
Property Subject to or Available for Operating Lease, Gross	1,259	1,226
Property Subject to or Available for Operating Lease, Accumulated Depreciation	(375)	(321)
Property Subject to or Available for Operating Lease, Net	$ 884	$ 905

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.

No definition available.

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- Definition

The amount of accumulated depreciation, by major property class, recorded on property subject to or available for lease as of the balance sheet date.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/otherTransitionRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=84164653&loc=d3e41551-112718

Reference 2: http://fasb.org/us-gaap/role/ref/otherTransitionRef
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-Section 45
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- Definition

Amount before accumulated depreciation of physical assets used in the normal conduct of business to produce goods and services subject to or available for lease.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/otherTransitionRef
-Publisher FASB
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- Definition

The amount of property, by major property class, net of accumulated depreciation, subject to or available for lease as of the balance sheet date.

+ References

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