v2.4.0.6

Goodwill (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011	Mar. 31, 2012	Dec. 31, 2011	Mar. 31, 2011	Dec. 31, 2010
Goodwill [Line Items]
Goodwill, beginning balance			$ 29,019
Impairment charges	0	0	(617)	(395)
Effect of foreign currency translation and other			3
Goodwill, ending balance	28,405		28,405
Accumulated impairment charges	(3,369)		(3,369)			(2,752)
Effect of adoption of ASU 2010-28				1,466
Automotive [Member]
Goodwill [Line Items]
Goodwill, beginning balance			27,741
Impairment charges	0	0	(617)	(395)
Effect of foreign currency translation and other			3
Goodwill, ending balance	27,127		27,127
Accumulated impairment charges	(3,369)		(3,369)			(2,752)
Effect of adoption of ASU 2010-28				1,466
Automotive [Member] | GMNA [Member]
Goodwill [Line Items]
Goodwill, beginning balance			26,399
Impairment charges	0	0	0	0
Effect of foreign currency translation and other			0
Goodwill, ending balance	26,399		26,399
Accumulated impairment charges	0		0			0
Effect of adoption of ASU 2010-28				0
Automotive [Member] | GME [Member]
Goodwill [Line Items]
Goodwill, beginning balance			581
Impairment charges	0	0	(590)	(395)
Effect of foreign currency translation and other			9
Goodwill, ending balance	0		0
Accumulated impairment charges	(3,072)		(3,072)			(2,482)
Effect of adoption of ASU 2010-28				1,466
Goodwill Before Impairment Charge					594		1,661	3,053
Weighted-Average Cost of Capital					17.50%		16.50%	17.00%
Long-Term Growth Rates					0.50%		0.50%	0.50%
Automotive [Member] | GME [Member] | Years 2011 and 2012 [Member]
Goodwill [Line Items]
Industry Vehicle Sales (in units)					19,100,000		18,400,000	18,400,000
Market Share					6.20%		6.60%	6.60%
Automotive [Member] | GME [Member] | Years 2015 and 2016 [Member]
Goodwill [Line Items]
Industry Vehicle Sales (in units)					21,900,000		22,000,000	22,000,000
Market Share					6.30%		7.40%	7.40%
Automotive [Member] | GMIO [Member]
Goodwill [Line Items]
Goodwill, beginning balance			610
Impairment charges	0	0	(27)	0
Effect of foreign currency translation and other			(1)
Goodwill, ending balance	582		582
Accumulated impairment charges	(297)		(297)			(270)
Effect of adoption of ASU 2010-28				0
Automotive [Member] | GMSA [Member]
Goodwill [Line Items]
Goodwill, beginning balance			151
Impairment charges	0	0	0	0
Effect of foreign currency translation and other			(5)
Goodwill, ending balance	146		146
Accumulated impairment charges	0		0			0
Effect of adoption of ASU 2010-28				0
Automotive [Member] | GM Korea [Member]
Goodwill [Line Items]
Goodwill Before Impairment Charge	523		523		564
Weighted-Average Cost of Capital	14.80%		14.80%		14.80%
Long-Term Growth Rates	3.00%		3.00%		3.00%
Automotive [Member] | GM Korea [Member] | Years 2011 and 2012 [Member]
Goodwill [Line Items]
Industry Vehicle Sales (in units)	81,000,000		81,000,000		81,000,000
Market Share	1.40%		1.40%		1.40%
Automotive [Member] | GM Korea [Member] | Years 2015 and 2016 [Member]
Goodwill [Line Items]
Industry Vehicle Sales (in units)	97,100,000		97,100,000		97,100,000
Market Share	1.10%		1.10%		1.10%
GM Financial [Member]
Goodwill [Line Items]
Goodwill, beginning balance			1,278
Impairment charges	0	0	0	0
Effect of foreign currency translation and other			0
Goodwill, ending balance	1,278		1,278
Accumulated impairment charges	0		0			0
Effect of adoption of ASU 2010-28				$ 0

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Carrying amount as of the balance sheet date, which is the cumulative amount paid and (if applicable) the fair value of any noncontrolling interest in the acquiree, adjusted for any amortization recognized prior to the adoption of any changes in generally accepted accounting principles (as applicable) and for any impairment charges, in excess of the fair value of net assets acquired in one or more business combination transactions.

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The accumulated impairment losses related to goodwill as of the balance sheet date.

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Loss recognized during the period that results from the write-down of goodwill after comparing the implied fair value of reporting unit goodwill with the carrying amount of that goodwill. Goodwill is assessed at least annually for impairment.

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The increase (decrease) to the recorded value of goodwill for foreign currency translation adjustments.

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Amount of the cumulative effect of the change in accounting principle or new accounting pronouncement on retained earnings or other components of equity or net assets in the statement of financial position as of the beginning of the earliest period presented.

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