Royalties And Licenses (Narrative) (Details) (USD $) In Millions				3 Months Ended		6 Months Ended		3 Months Ended
	Sep. 30, 2011	Mar. 31, 2011	Sep. 30, 2011 Fiscal 2011 Restructuring [Member]	Sep. 30, 2011 Fiscal 2011 Restructuring [Member] Amended Licensing Agreements [Member]	Sep. 30, 2010 Fiscal 2011 Restructuring [Member] Amended Licensing Agreements [Member]	Sep. 30, 2011 Fiscal 2011 Restructuring [Member] Amended Licensing Agreements [Member]	Sep. 30, 2010 Fiscal 2011 Restructuring [Member] Amended Licensing Agreements [Member]	Sep. 30, 2011 Developer Licensor Commitment [Member] Developer Performance Obligation Commitment [Member]
Royalties And Licenses [Line Items]
Loss and/or impairment charges on unrecognized minimum royalty-based commitments and long-lived royalty-based assets, respectively				$ 1	$ 0	$ 14	$ 10
Commitment to pay content licensors, independent software developers and co-publishing and/or distribution affiliates								926
Restructuring accrual included in royalty-related liabilities	$ 228	$ 197	$ 99