Short-Term and Long-Term Debt Short and Long-Term Debt (Details) - USD ($) $ in Millions	Sep. 30, 2015	Dec. 31, 2014
Automotive [Member]
Debt Instrument [Line Items]
Carrying amount	$ 9,144	$ 9,410
Fair Value	9,052	9,799
Automotive [Member] \| Level 1 [Member]
Debt Instrument [Line Items]
Fair Value	7,033	7,550
Automotive [Member] \| Level 2 [Member]
Debt Instrument [Line Items]
Fair Value	2,019	2,249
GM Financial [Member]
Debt Instrument [Line Items]
Carrying amount	48,259	37,431
Fair Value	48,193	37,707
GM Financial [Member] \| Secured Debt [Member]
Debt Instrument [Line Items]
Carrying amount	28,284	25,214
Fair Value	28,290	25,228
GM Financial [Member] \| Unsecured Debt [Member]
Debt Instrument [Line Items]
Carrying amount	19,975	12,217
Fair Value	19,903	12,479
GM Financial [Member] \| Level 2 [Member]
Debt Instrument [Line Items]
Fair Value	43,157	32,790
GM Financial [Member] \| Level 3 [Member]
Debt Instrument [Line Items]
Fair Value	$ 5,036	$ 4,917

Sum of the carrying values as of the balance sheet date of all debt, including all short-term borrowings, long-term debt, and capital lease obligations.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.13,16)

-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.7-03.16)

-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

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- Definition

Fair value portion of debt instrument payable, including, but not limited to, notes payable and loans payable.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 825

-SubTopic 10

-Section 50

-Paragraph 10

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=49121117&loc=d3e13433-108611

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 825

-SubTopic 10

-Section 50

-Paragraph 12

-URI http://asc.fasb.org/extlink&oid=49121117&loc=d3e13476-108611

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- Definition

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+ References

No definition available.

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