The number of credit facilities entered into.

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Number of New Credit Facilities

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Face (par) amount of debt instrument at time of issuance.

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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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No definition available.

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Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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No definition available.

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Weighted average interest rate of debt outstanding.

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No definition available.

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- Definition

Amount of contribution received by defined benefit plan from employer which increases plan assets.

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The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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Amount of increase (decrease) of the credit facility.

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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The cash outflow during the period from the repayment of aggregate short-term and long-term debt. Excludes payment of capital lease obligations.

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Automotive and GM Financial Debt Narrative (Details) $ in Millions	1 Months Ended		3 Months Ended	9 Months Ended
	Oct. 31, 2018 USD ($)	Apr. 30, 2018 USD ($) credit_faciliy	Sep. 30, 2018 USD ($)	Sep. 30, 2018 USD ($)	Mar. 31, 2018 USD ($)
Debt Instrument [Line Items]
Number of renewed credit facilities \| credit_faciliy		2
Number of new credit facilities \| credit_faciliy		1
Line of Credit [Member]
Debt Instrument [Line Items]
Aggregate borrowing capacity		$ 16,500			$ 14,500
Line of Credit [Member] \| Three Year Revolving Credit Facility April 2018 [Member]
Debt Instrument [Line Items]
Aggregate borrowing capacity		$ 4,000
Debt term		3 years
Line of Credit [Member] \| Letter of Credit [Member]
Debt Instrument [Line Items]
Aggregate borrowing capacity		$ 1,100
Line of Credit [Member] \| Five-Year Revolving Credit Facility April 2018 [Member]
Debt Instrument [Line Items]
Aggregate borrowing capacity		$ 10,500
Debt term		5 years
Unsecured Debt [Member] \| Senior Notes [Member]
Debt Instrument [Line Items]
Principal amount			$ 2,100	$ 2,100
Weighted average interest rate (percent)			5.03%	5.03%
GM Financial [Member] \| Line of Credit [Member] \| $2.0 Billion Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Aggregate borrowing capacity		$ 2,000
Debt term		364 days
GM Financial [Member] \| Secured Debt [Member] \| Line of Credit [Member] \| Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Total net additional borrowing capacity				$ 345
GM Financial [Member] \| Secured Debt [Member] \| Notes Payable, Other Payables [Member] \| Securitization notes payable [Member]
Debt Instrument [Line Items]
Principal amount			$ 16,300	$ 16,300
Weighted average interest rate (percent)			2.89%	2.89%
GM Financial [Member] \| Unsecured Debt [Member] \| Senior Notes [Member]
Debt Instrument [Line Items]
Principal amount			$ 7,200	$ 7,200
Weighted average interest rate (percent)			3.17%	3.17%
U.S. [Member] \| GM Financial [Member] \| Unsecured Debt [Member] \| Commercial Paper [Member]
Debt Instrument [Line Items]
Unsecured commercial paper			$ 1,500	$ 1,500
Non-U.S. [Member] \| U.K. and Canada [Member] \| Pension Plan [Member]
Debt Instrument [Line Items]
Contributions to pension plans			$ 584
Subsequent Event [Member]
Debt Instrument [Line Items]
Debt repayment	$ 1,500