Name:	gm_PolicyProductWarrantyAndRecallCampaignsAccrual
Namespace Prefix:	gm_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Increase or Decrease in standard product warranty liability and related liabilities due to currency translation and other. Does not include any Increase or Decrease in an extended product warranty liability due to currency translation.

No definition available.

Name:	gm_PolicyProductWarrantyAndRecallCampaignsAndCurrencyTranslationAndOtherIncreaseDecrease
Namespace Prefix:	gm_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

Policy Product Warranty And Recall Campaigns, Net Of Recoveries

No definition available.

Name:	gm_PolicyProductWarrantyAndRecallCampaignsNetOfRecoveries
Namespace Prefix:	gm_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Represents the aggregate decrease in the liability for payments made (in cash or in kind) to satisfy claims under the terms of the standard product warranty or related liabilities. Does not include any Increase or Decrease in the liability for payments related to extended product warranties.

No definition available.

Name:	gm_PolicyProductWarrantyAndRecallCampaignsPayments
Namespace Prefix:	gm_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

Represents the aggregate Increase or Decrease in the liability during the reporting period for accruals related to preexisting standard product warranties (including adjustments related to changes in estimates) and related liabilities. Does not include any Increase or Decrease in the liability for accruals related to extended product warranties.

No definition available.

Name:	gm_PolicyProductWarrantyAndRecallCampaignsPreExistingAdjustments
Namespace Prefix:	gm_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

Policy, Product Warranty Receivable, Supplier Recoveries

No definition available.

Name:	gm_PolicyProductWarrantyReceivableSupplierRecoveries
Namespace Prefix:	gm_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

Product Warranty Expense, Net Of Recoveries

No definition available.

Name:	gm_ProductWarrantyExpenseNetOfRecoveries
Namespace Prefix:	gm_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

Standard And Extended Product Warranty

No definition available.

Name:	gm_StandardAndExtendedProductWarrantyAbstract
Namespace Prefix:	gm_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

Standard And Extended Product Warranty Expense, Adjustments And Other

No definition available.

Name:	gm_StandardAndExtendedProductWarrantyExpenseAdjustmentsAndOther
Namespace Prefix:	gm_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

Standard And Extended Product Warranty Expense, Increase For Warranties Issued And Assumed In Period

No definition available.

Name:	gm_StandardAndExtendedProductWarrantyExpenseIncreaseForWarrantiesIssuedAndAssumedInPeriod
Namespace Prefix:	gm_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

Standard And Extended Product Warranty Expense, Supplier Recoveries Accrued In Period

No definition available.

Name:	gm_StandardAndExtendedProductWarrantyExpenseSupplierRecoveriesAccruedInPeriod
Namespace Prefix:	gm_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

Represents the aggregate increase in the liability for accruals related to warranty issued during the reporting period. Does not include any increase in the liability for accruals related to extended product warranties.

No definition available.

Name:	gm_WarrantiesIssuedAndAssumedInPeriodProductWarranty
Namespace Prefix:	gm_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

Represents the aggregate increase in the liability for accruals for recall campaigns and related liabilities issued during the reporting period.

No definition available.

Name:	gm_WarrantiesIssuedAndAssumedInPeriodRecallCampaigns
Namespace Prefix:	gm_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

No definition available.