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

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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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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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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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Equipment on Operating Leases (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2017
Property Subject to or Available for Operating Lease [Line Items]
Equipment on operating leases, net	$ 44,128		$ 44,128		$ 42,882
Operating Leases, Future Minimum Payments Receivable [Abstract]
Total	12,892		12,892
Vehicles [Member]
Property Subject to or Available for Operating Lease [Line Items]
Equipment on operating leases	55,840		55,840		53,947
Less: accumulated depreciation	(11,238)		(11,238)		(9,959)
Equipment on operating leases, net	44,602		44,602		43,988
Depreciation expense	1,900	$ 1,800	5,600	$ 4,900
Vehicles [Member] \| GM Financial [Member]
Property Subject to or Available for Operating Lease [Line Items]
Equipment on operating leases, net	44,100		44,100		$ 42,900
Operating Leases, Future Minimum Payments Receivable [Abstract]
2018	1,882		1,882
2019	6,260		6,260
2020	3,570		3,570
2021	1,077		1,077
2022	97		97
Thereafter	$ 6		$ 6