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.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
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-Section 45
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
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Future minimum rental payments in aggregate as of the balance sheet date under operating leases.

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Future rental payments receivable within the fifth year from the balance sheet date under an operating lease.

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Future rental payments receivable within the fourth year from the balance sheet date under an operating lease.

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Future rental payments receivable within the third year from the balance sheet date under an operating lease.

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Future rental payments receivable within the second year from the balance sheet date under an operating lease.

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Amount of required minimum rental payments receivable in the remainder of the fiscal year following the latest fiscal year ended for operating leases having an initial or remaining non-cancelable letter-terms in excess of one year.

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No definition available.

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Future minimum lease payments receivable under operating leases for periods greater than five years following the balance sheet date.

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

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (a)
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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.

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-Publisher FASB
-Name Accounting Standards Codification
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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.

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

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Equipment on Operating Leases (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017	Dec. 31, 2017
Property Subject to or Available for Operating Lease [Line Items]
Equipment on operating leases, net	$ 44,054		$ 44,054		$ 42,882
Operating Leases, Future Minimum Payments Receivable [Abstract]
Total	13,061		13,061
Vehicles [Member]
Property Subject to or Available for Operating Lease [Line Items]
Equipment on operating leases	55,570		55,570		53,947
Less: accumulated depreciation	(10,826)		(10,826)		(9,959)
Equipment on operating leases, net	44,744		44,744		43,988
Depreciation expense	1,800	$ 1,600	3,700	$ 3,100
Vehicles [Member] \| GM Financial [Member]
Property Subject to or Available for Operating Lease [Line Items]
Equipment on operating leases, net	44,054		44,054		$ 42,882
Operating Leases, Future Minimum Payments Receivable [Abstract]
2018	3,650		3,650
2019	5,709		5,709
2020	2,981		2,981
2021	667		667
2022	52		52
Thereafter	$ 2		$ 2