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

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_PolicyproductwarrantyrecallcampaignsandcourtesytransportationPayments
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_Policyproductwarrantyrecallcampaignsandcourtesytransportationpreexistingadjustments
Namespace Prefix:	gm_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

Represents the aggregate increase in the liability for accruals related to standard policy and 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_Warrantiesissuedandassumedinperiodpolicyandwarranty
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, courtesy transportation and related liabilities issued during the reporting period.

No definition available.

Name:	gm_Warrantiesissuedandassumedinperiodrecallcampaignsandcourtesytransportation
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.