Variable Interest Entities (Details) - GM Financial [Member] - USD ($) $ in Millions	Dec. 31, 2016	Dec. 31, 2015
Consolidated [Abstract]
GM Financial receivables, net of fees - current	$ 22,065	$ 18,051
GM Financial receivables, net of fees - non-current	20,724	18,500
GM Financial equipment on operating leases, net	34,526	20,172
GM Financial short-term debt and current portion of long-term debt	27,861	18,745
GM Financial long-term debt	46,015	35,601
Consolidated VIE [Member]
Consolidated [Abstract]
Restricted cash - current	1,532	1,345
Restricted cash - non-current	535	531
GM Financial receivables, net of fees - current	15,220	12,224
GM Financial receivables, net of fees - non-current	14,151	12,597
GM Financial equipment on operating leases, net	19,341	11,684
GM Financial short-term debt and current portion of long-term debt	20,005	13,545
GM Financial long-term debt	$ 18,239	$ 15,841

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Amount of short-term debt and current maturity of long-term debt and capital lease obligations due within one year or the normal operating cycle, if longer.

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An amount representing an agreement for an unconditional promise by the maker to pay the Company (holder) a definite sum of money within one year from the balance sheet date (or the normal operating cycle, whichever is longer), net of any write-downs taken for collection uncertainty on the part of the holder. Such amount may include accrued interest receivable in accordance with the terms of the debt. The debt also may contain provisions and related items including a discount or premium, payable on demand, secured, or unsecured, interest bearing or noninterest bearing, among a myriad of other features and characteristics. This amount does not include amounts related to receivables held-for-sale.

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An amount representing an agreement for an unconditional promise by the maker to pay the Entity (holder) a definite sum of money at a future date more than one year from the balance sheet date, net of any write-downs taken for collection uncertainty on the part of the holder. Such amount may include accrued interest receivable in accordance with the terms of the debt. The debt also may contain provisions and related items including a discount or premium, payable on demand, secured, or unsecured, interest bearing or noninterest bearing, among a myriad of other features and characteristics. This amount does not include amounts related to receivables held-for-sale.

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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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The current cash, cash equivalents and investments that are restricted as to withdrawal or usage. Restrictions may include legally restricted deposits held as compensating balances against short-term borrowing arrangements, contracts entered into with others, or entity statements of intention with regard to particular deposits; however, time deposits and short-term certificates of deposit are not generally included in legally restricted deposits. Excludes compensating balance arrangements that are not agreements which legally restrict the use of cash amounts shown on the balance sheet. Includes current cash equivalents and investments that are similarly restricted as to withdrawal, usage or disposal.

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