Variable Interest Entities (Details) - GM Financial [Member] - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018
Variable Interest Entity [Line Items]
GM Financial receivables, net of fees – current	$ 27,230	$ 26,850
GM Financial receivables, net of fees – non-current	25,448	25,083
GM Financial short-term debt and current portion of long-term debt	31,273	30,956
GM Financial long-term debt	60,858	60,032
Consolidated VIE [Member]
Variable Interest Entity [Line Items]
Restricted cash – current	2,209	1,876
Restricted cash – non-current	473	504
GM Financial receivables, net of fees – current	18,283	18,304
GM Financial receivables, net of fees – non-current	13,448	14,008
GM Financial equipment on operating leases, net	20,313	21,781
GM Financial short-term debt and current portion of long-term debt	21,832	21,087
GM Financial long-term debt	$ 19,523	$ 21,417

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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Amount of long-term debt and capital lease obligation due after one year or beyond 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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The noncurrent cash, cash equivalents and investments that is restricted as to withdrawal or usage. Restrictions may include legally restricted deposits held as compensating balances against borrowing arrangements, contracts entered into with others, or entity statements of intention with regard to particular deposits classified as long-term; that is not expected to be released from such existing restrictions within one year of the balance sheet date or operating cycle, whichever is longer. Excludes compensating balance arrangements that are not agreements which legally restrict the use of cash amounts shown on the balance sheet. Includes noncurrent cash equivalents and investments that are similarly restricted as to withdrawal, usage or disposal.

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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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