Variable Interest Entities (Details) - USD ($) $ in Millions	Sep. 30, 2017	Dec. 31, 2016
Variable Interest Entity [Line Items]
GM Financial equipment on operating leases, net	$ 41,775	$ 34,342
GM Financial [Member]
Variable Interest Entity [Line Items]
GM Financial receivables, net of fees – current	19,399	16,127
GM Financial receivables, net of fees – non-current	21,021	17,001
GM Financial short-term debt and current portion of long-term debt	24,480	22,737
GM Financial long-term debt	54,558	41,826
Consolidated VIE [Member] | GM Financial [Member]
Variable Interest Entity [Line Items]
Restricted cash – current	1,768	1,302
Restricted cash – non-current	523	478
GM Financial receivables, net of fees – current	13,782	12,437
GM Financial receivables, net of fees – non-current	12,411	11,917
GM Financial equipment on operating leases, net	23,751	19,341
GM Financial short-term debt and current portion of long-term debt	19,207	17,526
GM Financial long-term debt	$ 20,981	$ 16,659