Intangible assets, net (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended			9 Months Ended	12 Months Ended		9 Months Ended	12 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011	Dec. 31, 2011	Sep. 30, 2012 License agreements	Dec. 31, 2011 License agreements	Dec. 31, 2011 Game engines	Sep. 30, 2012 Internally developed franchises	Dec. 31, 2011 Internally developed franchises	Dec. 31, 2011 Distribution agreements	Sep. 30, 2012 Activision trademark	Dec. 31, 2011 Activision trademark	Sep. 30, 2012 Acquired trade names	Dec. 31, 2011 Acquired trade names
Definite-lived intangible assets
Estimated useful life, minimum (in years)						3	3	2	11	11	4
Estimated useful life, maximum (in years)						10	10	5	12	12	4
Gross carrying amount, definite-lived intangible assets						$ 88	$ 88	$ 32	$ 309	$ 309	$ 18
Accumulated amortization, definite-lived intangible assets	(317)		(317)		(359)	(84)	(82)	(32)	(233)	(227)	(18)
Net carrying amount, definite-lived intangible assets	80		80		88	4	6	0	76	82	0
Gross carrying amount, intangible assets excluding goodwill	830		830		880
Net carrying amount, intangible assets	513		513		521
Indefinite-lived intangible assets
Carrying amount, indefinite-lived intangible assets												386	386	47	47
Amortization expense disclosure
Amortization expense	3	7	7	22
Definite-lived intangible assets, future amortization expense disclosure
2012 (remaining three months)			27
2013			28
2014			13
2015			7
2016			3
Thereafter			2
Total			$ 80