Leasing Leasing (Schedule of Property Subject to or Available for Operating Lease) (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2019	Dec. 31, 2018
Property Subject to or Available for Operating Lease, Net [Abstract]
Operating leases with a residual value guarantee	$ 394
Lessor, operating lease, lessee option to purchase underlying asset, minimum lease term	24 months
Residual value guarantee	15.00%
Vehicles available for operating lease, gross	$ 9,903	$ 9,995
Vehicles available for operating lease, accumulated depreciation	(1,564)	(1,578)
Investment in operating leases, net	$ 8,339	$ 8,417
Lessor, operating lease, lessee option to purchase underlying asset, maximum lease term	60 months

Lessor, operating lease, lessee option to purchase underlying asset, maximum lease term

No definition available.

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- Definition

Lessor, operating lease, lessee option to purchase underlying asset, minimum lease term

+ References

No definition available.

+ Details

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- Definition

Operating leases with a residual value guarantee

+ References

No definition available.

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- Definition

Residual value guarantee

+ References

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/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 20
-Section 45
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=77907726&loc=d3e41460-112716

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-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

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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/legacyRef
-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/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 20
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=77907726&loc=d3e41457-112716

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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

+ Details

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- References

No definition available.

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